diff --git a/NEWS b/NEWS
index d25aa407..0cf48194 100644
--- a/NEWS
+++ b/NEWS
@@ -15,7 +15,7 @@ NEWS ( CHANGELOG and HISTORY )                                     HTMLPurifier
   to it.
   + Visibility declarations added
   + Constructor methods renamed to __construct()
-  + PHP4 reference/foreach cruft removed (in progress)
+  + PHP4 reference cruft removed (in progress)
 ! CSS properties are no case-insensitive
 ! DefinitionCacheFactory now can register new implementations
 ! New HTMLPurifier_Filter_ExtractStyleBlocks for extracting <style> from
@@ -31,6 +31,7 @@ NEWS ( CHANGELOG and HISTORY )                                     HTMLPurifier
 . New classes:
   + HTMLPurifier_AttrDef_CSS_AlphaValue
   + HTMLPurifier_AttrDef_CSS_Filter
+. Multitest now has a file docblock
 
 2.1.3, released 2007-11-05
 ! tests/multitest.php allows you to test multiple versions by running
diff --git a/TODO b/TODO
index 4061512a..d6d47ac3 100644
--- a/TODO
+++ b/TODO
@@ -12,7 +12,6 @@ amount of effort to implement, it may get endlessly delayed. Do not be
 afraid to cast your vote for the next feature to be implemented!
 
 3.0 release [Go PHP5!]
- - Convert all &$context calls to $context, as PHP5 passes objects by value
  - Allow extracted CSS blocks to have a bounding selector prepended to all
    of their declarations. There are two types: a global type and a HTML5
    scoped type. This will allow for <style> while minimizing the risk of
@@ -61,10 +60,10 @@ afraid to cast your vote for the next feature to be implemented!
     - Lots of documentation and samples
 
 Ongoing
+ - More refactoring to take advantage of PHP5's facilities 
  - Lots of profiling, make it faster!
  - Plugins for major CMSes (COMPLEX)
     - phpBB
-    - eFiction
     - more! (look for ones that use WYSIWYGs)
  - Complete basic smoketests
 
@@ -75,6 +74,8 @@ AutoFormat
 
 Unknown release (on a scratch-an-itch basis)
  # CHMOD install script for PEAR installs
+ # Convert multitest to use the XML format
+ # Make test/index.php have better cli flags
  ? Have 'lang' attribute be checked against official lists, achieved by
    encoding all characters that have string entity equivalents
  - Abstract ChildDef_BlockQuote to work with all elements that only
diff --git a/library/HTMLPurifier/AttrDef.php b/library/HTMLPurifier/AttrDef.php
index 2ee090f4..f29c933c 100644
--- a/library/HTMLPurifier/AttrDef.php
+++ b/library/HTMLPurifier/AttrDef.php
@@ -32,7 +32,7 @@ abstract class HTMLPurifier_AttrDef
      * @param $config Mandatory HTMLPurifier_Config object.
      * @param $context Mandatory HTMLPurifier_AttrContext object.
      */
-    abstract public function validate($string, $config, &$context);
+    abstract public function validate($string, $config, $context);
     
     /**
      * Convenience method that parses a string as if it were CDATA.
diff --git a/library/HTMLPurifier/AttrDef/CSS.php b/library/HTMLPurifier/AttrDef/CSS.php
index f986e012..c5ab4972 100644
--- a/library/HTMLPurifier/AttrDef/CSS.php
+++ b/library/HTMLPurifier/AttrDef/CSS.php
@@ -17,7 +17,7 @@ require_once 'HTMLPurifier/CSSDefinition.php';
 class HTMLPurifier_AttrDef_CSS extends HTMLPurifier_AttrDef
 {
     
-    public function validate($css, $config, &$context) {
+    public function validate($css, $config, $context) {
         
         $css = $this->parseCDATA($css);
         
diff --git a/library/HTMLPurifier/AttrDef/CSS/AlphaValue.php b/library/HTMLPurifier/AttrDef/CSS/AlphaValue.php
index 2492ee2e..45f51a4b 100644
--- a/library/HTMLPurifier/AttrDef/CSS/AlphaValue.php
+++ b/library/HTMLPurifier/AttrDef/CSS/AlphaValue.php
@@ -10,7 +10,7 @@ class HTMLPurifier_AttrDef_CSS_AlphaValue extends HTMLPurifier_AttrDef_CSS_Numbe
         parent::__construct(false); // opacity is non-negative, but we will clamp it
     }
     
-    public function validate($number, $config, &$context) {
+    public function validate($number, $config, $context) {
         $result = parent::validate($number, $config, $context);
         if ($result === false) return $result;
         $float = (float) $result;
diff --git a/library/HTMLPurifier/AttrDef/CSS/Background.php b/library/HTMLPurifier/AttrDef/CSS/Background.php
index 9812c7b2..25aff2cd 100644
--- a/library/HTMLPurifier/AttrDef/CSS/Background.php
+++ b/library/HTMLPurifier/AttrDef/CSS/Background.php
@@ -25,7 +25,7 @@ class HTMLPurifier_AttrDef_CSS_Background extends HTMLPurifier_AttrDef
         $this->info['background-position'] = $def->info['background-position'];
     }
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         
         // regular pre-processing
         $string = $this->parseCDATA($string);
diff --git a/library/HTMLPurifier/AttrDef/CSS/BackgroundPosition.php b/library/HTMLPurifier/AttrDef/CSS/BackgroundPosition.php
index 38319926..876d9f4c 100644
--- a/library/HTMLPurifier/AttrDef/CSS/BackgroundPosition.php
+++ b/library/HTMLPurifier/AttrDef/CSS/BackgroundPosition.php
@@ -56,7 +56,7 @@ class HTMLPurifier_AttrDef_CSS_BackgroundPosition extends HTMLPurifier_AttrDef
         $this->percentage = new HTMLPurifier_AttrDef_CSS_Percentage();
     }
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         $string = $this->parseCDATA($string);
         $bits = explode(' ', $string);
         
diff --git a/library/HTMLPurifier/AttrDef/CSS/Border.php b/library/HTMLPurifier/AttrDef/CSS/Border.php
index 63640519..01bdcd67 100644
--- a/library/HTMLPurifier/AttrDef/CSS/Border.php
+++ b/library/HTMLPurifier/AttrDef/CSS/Border.php
@@ -20,7 +20,7 @@ class HTMLPurifier_AttrDef_CSS_Border extends HTMLPurifier_AttrDef
         $this->info['border-top-color'] = $def->info['border-top-color'];
     }
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         $string = $this->parseCDATA($string);
         // we specifically will not support rgb() syntax with spaces
         $bits = explode(' ', $string);
diff --git a/library/HTMLPurifier/AttrDef/CSS/Color.php b/library/HTMLPurifier/AttrDef/CSS/Color.php
index b86dc091..34d56fa9 100644
--- a/library/HTMLPurifier/AttrDef/CSS/Color.php
+++ b/library/HTMLPurifier/AttrDef/CSS/Color.php
@@ -33,7 +33,7 @@ This directive has been available since 2.0.0.
 class HTMLPurifier_AttrDef_CSS_Color extends HTMLPurifier_AttrDef
 {
     
-    public function validate($color, $config, &$context) {
+    public function validate($color, $config, $context) {
         
         static $colors = null;
         if ($colors === null) $colors = $config->get('Core', 'ColorKeywords');
diff --git a/library/HTMLPurifier/AttrDef/CSS/Composite.php b/library/HTMLPurifier/AttrDef/CSS/Composite.php
index 1b6c8ad4..c9650699 100644
--- a/library/HTMLPurifier/AttrDef/CSS/Composite.php
+++ b/library/HTMLPurifier/AttrDef/CSS/Composite.php
@@ -25,7 +25,7 @@ class HTMLPurifier_AttrDef_CSS_Composite extends HTMLPurifier_AttrDef
         $this->defs = $defs;
     }
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         foreach ($this->defs as $i => $def) {
             $result = $this->defs[$i]->validate($string, $config, $context);
             if ($result !== false) return $result;
diff --git a/library/HTMLPurifier/AttrDef/CSS/Filter.php b/library/HTMLPurifier/AttrDef/CSS/Filter.php
index 7f46688c..61da7911 100644
--- a/library/HTMLPurifier/AttrDef/CSS/Filter.php
+++ b/library/HTMLPurifier/AttrDef/CSS/Filter.php
@@ -17,7 +17,7 @@ class HTMLPurifier_AttrDef_CSS_Filter extends HTMLPurifier_AttrDef
         $this->intValidator = new HTMLPurifier_AttrDef_Integer();
     }
     
-    public function validate($value, $config, &$context) {
+    public function validate($value, $config, $context) {
         $value = $this->parseCDATA($value);
         if ($value === 'none') return $value;
         // if we looped this we could support multiple filters
diff --git a/library/HTMLPurifier/AttrDef/CSS/Font.php b/library/HTMLPurifier/AttrDef/CSS/Font.php
index 2b6b6795..208bd2eb 100644
--- a/library/HTMLPurifier/AttrDef/CSS/Font.php
+++ b/library/HTMLPurifier/AttrDef/CSS/Font.php
@@ -28,7 +28,7 @@ class HTMLPurifier_AttrDef_CSS_Font extends HTMLPurifier_AttrDef
         $this->info['font-family']  = $def->info['font-family'];
     }
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         
         static $system_fonts = array(
             'caption' => true,
diff --git a/library/HTMLPurifier/AttrDef/CSS/FontFamily.php b/library/HTMLPurifier/AttrDef/CSS/FontFamily.php
index 536149b4..827dd4d9 100644
--- a/library/HTMLPurifier/AttrDef/CSS/FontFamily.php
+++ b/library/HTMLPurifier/AttrDef/CSS/FontFamily.php
@@ -10,7 +10,7 @@ require_once 'HTMLPurifier/AttrDef.php';
 class HTMLPurifier_AttrDef_CSS_FontFamily extends HTMLPurifier_AttrDef
 {
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         static $generic_names = array(
             'serif' => true,
             'sans-serif' => true,
diff --git a/library/HTMLPurifier/AttrDef/CSS/Length.php b/library/HTMLPurifier/AttrDef/CSS/Length.php
index 222bc1bd..def47376 100644
--- a/library/HTMLPurifier/AttrDef/CSS/Length.php
+++ b/library/HTMLPurifier/AttrDef/CSS/Length.php
@@ -29,7 +29,7 @@ class HTMLPurifier_AttrDef_CSS_Length extends HTMLPurifier_AttrDef
         $this->number_def = new HTMLPurifier_AttrDef_CSS_Number($non_negative);
     }
     
-    public function validate($length, $config, &$context) {
+    public function validate($length, $config, $context) {
         
         $length = $this->parseCDATA($length);
         if ($length === '') return false;
diff --git a/library/HTMLPurifier/AttrDef/CSS/ListStyle.php b/library/HTMLPurifier/AttrDef/CSS/ListStyle.php
index 99e044a1..722cf052 100644
--- a/library/HTMLPurifier/AttrDef/CSS/ListStyle.php
+++ b/library/HTMLPurifier/AttrDef/CSS/ListStyle.php
@@ -22,7 +22,7 @@ class HTMLPurifier_AttrDef_CSS_ListStyle extends HTMLPurifier_AttrDef
         $this->info['list-style-image'] = $def->info['list-style-image'];
     }
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         
         // regular pre-processing
         $string = $this->parseCDATA($string);
diff --git a/library/HTMLPurifier/AttrDef/CSS/Multiple.php b/library/HTMLPurifier/AttrDef/CSS/Multiple.php
index e41637e2..3488f0b6 100644
--- a/library/HTMLPurifier/AttrDef/CSS/Multiple.php
+++ b/library/HTMLPurifier/AttrDef/CSS/Multiple.php
@@ -37,7 +37,7 @@ class HTMLPurifier_AttrDef_CSS_Multiple extends HTMLPurifier_AttrDef
         $this->max = $max;
     }
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         $string = $this->parseCDATA($string);
         if ($string === '') return false;
         $parts = explode(' ', $string); // parseCDATA replaced \r, \t and \n
diff --git a/library/HTMLPurifier/AttrDef/CSS/Number.php b/library/HTMLPurifier/AttrDef/CSS/Number.php
index c5f46399..3d4028ee 100644
--- a/library/HTMLPurifier/AttrDef/CSS/Number.php
+++ b/library/HTMLPurifier/AttrDef/CSS/Number.php
@@ -18,7 +18,7 @@ class HTMLPurifier_AttrDef_CSS_Number extends HTMLPurifier_AttrDef
         $this->non_negative = $non_negative;
     }
     
-    public function validate($number, $config, &$context) {
+    public function validate($number, $config, $context) {
         
         $number = $this->parseCDATA($number);
         
diff --git a/library/HTMLPurifier/AttrDef/CSS/Percentage.php b/library/HTMLPurifier/AttrDef/CSS/Percentage.php
index 3804a0a9..cf01a72f 100644
--- a/library/HTMLPurifier/AttrDef/CSS/Percentage.php
+++ b/library/HTMLPurifier/AttrDef/CSS/Percentage.php
@@ -21,7 +21,7 @@ class HTMLPurifier_AttrDef_CSS_Percentage extends HTMLPurifier_AttrDef
         $this->number_def = new HTMLPurifier_AttrDef_CSS_Number($non_negative);
     }
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         
         $string = $this->parseCDATA($string);
         
diff --git a/library/HTMLPurifier/AttrDef/CSS/TextDecoration.php b/library/HTMLPurifier/AttrDef/CSS/TextDecoration.php
index ed076f07..2aea4563 100644
--- a/library/HTMLPurifier/AttrDef/CSS/TextDecoration.php
+++ b/library/HTMLPurifier/AttrDef/CSS/TextDecoration.php
@@ -10,7 +10,7 @@ require_once 'HTMLPurifier/AttrDef.php';
 class HTMLPurifier_AttrDef_CSS_TextDecoration extends HTMLPurifier_AttrDef
 {
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         
         static $allowed_values = array(
             'line-through' => true,
diff --git a/library/HTMLPurifier/AttrDef/CSS/URI.php b/library/HTMLPurifier/AttrDef/CSS/URI.php
index b4b87174..ea1d0adb 100644
--- a/library/HTMLPurifier/AttrDef/CSS/URI.php
+++ b/library/HTMLPurifier/AttrDef/CSS/URI.php
@@ -18,7 +18,7 @@ class HTMLPurifier_AttrDef_CSS_URI extends HTMLPurifier_AttrDef_URI
         parent::__construct(true); // always embedded
     }
     
-    public function validate($uri_string, $config, &$context) {
+    public function validate($uri_string, $config, $context) {
         // parse the URI out of the string and then pass it onto
         // the parent object
         
diff --git a/library/HTMLPurifier/AttrDef/Enum.php b/library/HTMLPurifier/AttrDef/Enum.php
index 1219b593..a28b4457 100644
--- a/library/HTMLPurifier/AttrDef/Enum.php
+++ b/library/HTMLPurifier/AttrDef/Enum.php
@@ -35,7 +35,7 @@ class HTMLPurifier_AttrDef_Enum extends HTMLPurifier_AttrDef
         $this->case_sensitive = $case_sensitive;
     }
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         $string = trim($string);
         if (!$this->case_sensitive) {
             // we may want to do full case-insensitive libraries
diff --git a/library/HTMLPurifier/AttrDef/HTML/Bool.php b/library/HTMLPurifier/AttrDef/HTML/Bool.php
index 5962d91f..486ca85d 100644
--- a/library/HTMLPurifier/AttrDef/HTML/Bool.php
+++ b/library/HTMLPurifier/AttrDef/HTML/Bool.php
@@ -13,7 +13,7 @@ class HTMLPurifier_AttrDef_HTML_Bool extends HTMLPurifier_AttrDef
     
     public function __construct($name = false) {$this->name = $name;}
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         if (empty($string)) return false;
         return $this->name;
     }
diff --git a/library/HTMLPurifier/AttrDef/HTML/Color.php b/library/HTMLPurifier/AttrDef/HTML/Color.php
index 36385193..14313d5b 100644
--- a/library/HTMLPurifier/AttrDef/HTML/Color.php
+++ b/library/HTMLPurifier/AttrDef/HTML/Color.php
@@ -9,7 +9,7 @@ require_once 'HTMLPurifier/AttrDef/CSS/Color.php'; // for %Core.ColorKeywords
 class HTMLPurifier_AttrDef_HTML_Color extends HTMLPurifier_AttrDef
 {
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         
         static $colors = null;
         if ($colors === null) $colors = $config->get('Core', 'ColorKeywords');
diff --git a/library/HTMLPurifier/AttrDef/HTML/FrameTarget.php b/library/HTMLPurifier/AttrDef/HTML/FrameTarget.php
index 0bb2f47d..30eb7da0 100644
--- a/library/HTMLPurifier/AttrDef/HTML/FrameTarget.php
+++ b/library/HTMLPurifier/AttrDef/HTML/FrameTarget.php
@@ -24,7 +24,7 @@ class HTMLPurifier_AttrDef_HTML_FrameTarget extends HTMLPurifier_AttrDef_Enum
     
     public function __construct() {}
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         if ($this->valid_values === false) $this->valid_values = $config->get('Attr', 'AllowedFrameTargets');
         return parent::validate($string, $config, $context);
     }
diff --git a/library/HTMLPurifier/AttrDef/HTML/ID.php b/library/HTMLPurifier/AttrDef/HTML/ID.php
index 89836fd0..fd0b7aaa 100644
--- a/library/HTMLPurifier/AttrDef/HTML/ID.php
+++ b/library/HTMLPurifier/AttrDef/HTML/ID.php
@@ -66,7 +66,7 @@ class HTMLPurifier_AttrDef_HTML_ID extends HTMLPurifier_AttrDef
     // ref functionality disabled, since we also have to verify
     // whether or not the ID it refers to exists
     
-    public function validate($id, $config, &$context) {
+    public function validate($id, $config, $context) {
         
         if (!$config->get('Attr', 'EnableID')) return false;
         
diff --git a/library/HTMLPurifier/AttrDef/HTML/Length.php b/library/HTMLPurifier/AttrDef/HTML/Length.php
index bc844ca2..32a2b864 100644
--- a/library/HTMLPurifier/AttrDef/HTML/Length.php
+++ b/library/HTMLPurifier/AttrDef/HTML/Length.php
@@ -13,7 +13,7 @@ require_once 'HTMLPurifier/AttrDef/HTML/Pixels.php';
 class HTMLPurifier_AttrDef_HTML_Length extends HTMLPurifier_AttrDef_HTML_Pixels
 {
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         
         $string = trim($string);
         if ($string === '') return false;
diff --git a/library/HTMLPurifier/AttrDef/HTML/LinkTypes.php b/library/HTMLPurifier/AttrDef/HTML/LinkTypes.php
index d8a128ab..f2684130 100644
--- a/library/HTMLPurifier/AttrDef/HTML/LinkTypes.php
+++ b/library/HTMLPurifier/AttrDef/HTML/LinkTypes.php
@@ -42,7 +42,7 @@ class HTMLPurifier_AttrDef_HTML_LinkTypes extends HTMLPurifier_AttrDef
         $this->name = $configLookup[$name];
     }
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         
         $allowed = $config->get('Attr', $this->name);
         if (empty($allowed)) return false;
diff --git a/library/HTMLPurifier/AttrDef/HTML/MultiLength.php b/library/HTMLPurifier/AttrDef/HTML/MultiLength.php
index 3419d1da..54ae4f1e 100644
--- a/library/HTMLPurifier/AttrDef/HTML/MultiLength.php
+++ b/library/HTMLPurifier/AttrDef/HTML/MultiLength.php
@@ -12,7 +12,7 @@ require_once 'HTMLPurifier/AttrDef/HTML/Length.php';
 class HTMLPurifier_AttrDef_HTML_MultiLength extends HTMLPurifier_AttrDef_HTML_Length
 {
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         
         $string = trim($string);
         if ($string === '') return false;
diff --git a/library/HTMLPurifier/AttrDef/HTML/Nmtokens.php b/library/HTMLPurifier/AttrDef/HTML/Nmtokens.php
index 3974dab5..4d8f3c9c 100644
--- a/library/HTMLPurifier/AttrDef/HTML/Nmtokens.php
+++ b/library/HTMLPurifier/AttrDef/HTML/Nmtokens.php
@@ -13,7 +13,7 @@ require_once 'HTMLPurifier/Config.php';
 class HTMLPurifier_AttrDef_HTML_Nmtokens extends HTMLPurifier_AttrDef
 {
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         
         $string = trim($string);
         
diff --git a/library/HTMLPurifier/AttrDef/HTML/Pixels.php b/library/HTMLPurifier/AttrDef/HTML/Pixels.php
index 0b6df9e2..ed51dfa7 100644
--- a/library/HTMLPurifier/AttrDef/HTML/Pixels.php
+++ b/library/HTMLPurifier/AttrDef/HTML/Pixels.php
@@ -8,7 +8,7 @@ require_once 'HTMLPurifier/AttrDef.php';
 class HTMLPurifier_AttrDef_HTML_Pixels extends HTMLPurifier_AttrDef
 {
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         
         $string = trim($string);
         if ($string === '0') return $string;
diff --git a/library/HTMLPurifier/AttrDef/Integer.php b/library/HTMLPurifier/AttrDef/Integer.php
index 68385d0e..6ecdebca 100644
--- a/library/HTMLPurifier/AttrDef/Integer.php
+++ b/library/HTMLPurifier/AttrDef/Integer.php
@@ -40,7 +40,7 @@ class HTMLPurifier_AttrDef_Integer extends HTMLPurifier_AttrDef
         $this->positive = $positive;
     }
     
-    public function validate($integer, $config, &$context) {
+    public function validate($integer, $config, $context) {
         
         $integer = $this->parseCDATA($integer);
         if ($integer === '') return false;
diff --git a/library/HTMLPurifier/AttrDef/Lang.php b/library/HTMLPurifier/AttrDef/Lang.php
index 53c95db8..afbf4d1f 100644
--- a/library/HTMLPurifier/AttrDef/Lang.php
+++ b/library/HTMLPurifier/AttrDef/Lang.php
@@ -9,7 +9,7 @@ require_once 'HTMLPurifier/AttrDef.php';
 class HTMLPurifier_AttrDef_Lang extends HTMLPurifier_AttrDef
 {
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         
         $string = trim($string);
         if (!$string) return false;
diff --git a/library/HTMLPurifier/AttrDef/Text.php b/library/HTMLPurifier/AttrDef/Text.php
index f0091434..d5e0e7b7 100644
--- a/library/HTMLPurifier/AttrDef/Text.php
+++ b/library/HTMLPurifier/AttrDef/Text.php
@@ -8,7 +8,7 @@ require_once 'HTMLPurifier/AttrDef.php';
 class HTMLPurifier_AttrDef_Text extends HTMLPurifier_AttrDef
 {
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         return $this->parseCDATA($string);
     }
     
diff --git a/library/HTMLPurifier/AttrDef/URI.php b/library/HTMLPurifier/AttrDef/URI.php
index 7bb3af50..710abaa6 100644
--- a/library/HTMLPurifier/AttrDef/URI.php
+++ b/library/HTMLPurifier/AttrDef/URI.php
@@ -80,7 +80,7 @@ class HTMLPurifier_AttrDef_URI extends HTMLPurifier_AttrDef
         $this->embedsResource = (bool) $embeds_resource;
     }
     
-    public function validate($uri, $config, &$context) {
+    public function validate($uri, $config, $context) {
         
         if ($config->get('URI', 'Disable')) return false;
         
diff --git a/library/HTMLPurifier/AttrDef/URI/Email/SimpleCheck.php b/library/HTMLPurifier/AttrDef/URI/Email/SimpleCheck.php
index 9700242a..c8b58d4b 100644
--- a/library/HTMLPurifier/AttrDef/URI/Email/SimpleCheck.php
+++ b/library/HTMLPurifier/AttrDef/URI/Email/SimpleCheck.php
@@ -9,7 +9,7 @@ require_once 'HTMLPurifier/AttrDef/URI/Email.php';
 class HTMLPurifier_AttrDef_URI_Email_SimpleCheck extends HTMLPurifier_AttrDef_URI_Email
 {
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         // no support for named mailboxes i.e. "Bob <bob@example.com>"
         // that needs more percent encoding to be done
         if ($string == '') return false;
diff --git a/library/HTMLPurifier/AttrDef/URI/Host.php b/library/HTMLPurifier/AttrDef/URI/Host.php
index 635b40de..3451917d 100644
--- a/library/HTMLPurifier/AttrDef/URI/Host.php
+++ b/library/HTMLPurifier/AttrDef/URI/Host.php
@@ -25,7 +25,7 @@ class HTMLPurifier_AttrDef_URI_Host extends HTMLPurifier_AttrDef
         $this->ipv6 = new HTMLPurifier_AttrDef_URI_IPv6();
     }
     
-    public function validate($string, $config, &$context) {
+    public function validate($string, $config, $context) {
         $length = strlen($string);
         if ($string === '') return '';
         if ($length > 1 && $string[0] === '[' && $string[$length-1] === ']') {
diff --git a/library/HTMLPurifier/AttrDef/URI/IPv4.php b/library/HTMLPurifier/AttrDef/URI/IPv4.php
index 7550f1d6..d622440f 100644
--- a/library/HTMLPurifier/AttrDef/URI/IPv4.php
+++ b/library/HTMLPurifier/AttrDef/URI/IPv4.php
@@ -14,7 +14,7 @@ class HTMLPurifier_AttrDef_URI_IPv4 extends HTMLPurifier_AttrDef
      */
     protected $ip4;
     
-    public function validate($aIP, $config, &$context) {
+    public function validate($aIP, $config, $context) {
         
         if (!$this->ip4) $this->_loadRegex();
         
diff --git a/library/HTMLPurifier/AttrDef/URI/IPv6.php b/library/HTMLPurifier/AttrDef/URI/IPv6.php
index 5dc4a29b..3f597520 100644
--- a/library/HTMLPurifier/AttrDef/URI/IPv6.php
+++ b/library/HTMLPurifier/AttrDef/URI/IPv6.php
@@ -11,7 +11,7 @@ require_once 'HTMLPurifier/AttrDef/URI/IPv4.php';
 class HTMLPurifier_AttrDef_URI_IPv6 extends HTMLPurifier_AttrDef_URI_IPv4
 {
     
-    public function validate($aIP, $config, &$context) {
+    public function validate($aIP, $config, $context) {
         
         if (!$this->ip4) $this->_loadRegex();
         
diff --git a/library/HTMLPurifier/AttrTransform.php b/library/HTMLPurifier/AttrTransform.php
index 2f1cef6e..a295c985 100644
--- a/library/HTMLPurifier/AttrTransform.php
+++ b/library/HTMLPurifier/AttrTransform.php
@@ -26,7 +26,7 @@ abstract class HTMLPurifier_AttrTransform
      * @param $context Mandatory HTMLPurifier_Context object
      * @returns Processed attribute array.
      */
-    abstract public function transform($attr, $config, &$context);
+    abstract public function transform($attr, $config, $context);
     
     /**
      * Prepends CSS properties to the style attribute, creating the
diff --git a/library/HTMLPurifier/AttrTransform/BdoDir.php b/library/HTMLPurifier/AttrTransform/BdoDir.php
index fdaf33d3..15f9188e 100644
--- a/library/HTMLPurifier/AttrTransform/BdoDir.php
+++ b/library/HTMLPurifier/AttrTransform/BdoDir.php
@@ -20,7 +20,7 @@ HTMLPurifier_ConfigSchema::defineAllowedValues(
 class HTMLPurifier_AttrTransform_BdoDir extends HTMLPurifier_AttrTransform
 {
     
-    public function transform($attr, $config, &$context) {
+    public function transform($attr, $config, $context) {
         if (isset($attr['dir'])) return $attr;
         $attr['dir'] = $config->get('Attr', 'DefaultTextDir');
         return $attr;
diff --git a/library/HTMLPurifier/AttrTransform/BgColor.php b/library/HTMLPurifier/AttrTransform/BgColor.php
index cbcc63f7..5962a6e5 100644
--- a/library/HTMLPurifier/AttrTransform/BgColor.php
+++ b/library/HTMLPurifier/AttrTransform/BgColor.php
@@ -7,7 +7,7 @@ require_once 'HTMLPurifier/AttrTransform.php';
  */
 class HTMLPurifier_AttrTransform_BgColor extends HTMLPurifier_AttrTransform {
 
-    public function transform($attr, $config, &$context) {
+    public function transform($attr, $config, $context) {
         
         if (!isset($attr['bgcolor'])) return $attr;
         
diff --git a/library/HTMLPurifier/AttrTransform/BoolToCSS.php b/library/HTMLPurifier/AttrTransform/BoolToCSS.php
index a7e793ab..bb1b8b65 100644
--- a/library/HTMLPurifier/AttrTransform/BoolToCSS.php
+++ b/library/HTMLPurifier/AttrTransform/BoolToCSS.php
@@ -27,7 +27,7 @@ extends HTMLPurifier_AttrTransform {
         $this->css  = $css;
     }
     
-    public function transform($attr, $config, &$context) {
+    public function transform($attr, $config, $context) {
         if (!isset($attr[$this->attr])) return $attr;
         unset($attr[$this->attr]);
         $this->prependCSS($attr, $this->css);
diff --git a/library/HTMLPurifier/AttrTransform/Border.php b/library/HTMLPurifier/AttrTransform/Border.php
index 1dd5a046..debf6f20 100644
--- a/library/HTMLPurifier/AttrTransform/Border.php
+++ b/library/HTMLPurifier/AttrTransform/Border.php
@@ -7,7 +7,7 @@ require_once 'HTMLPurifier/AttrTransform.php';
  */
 class HTMLPurifier_AttrTransform_Border extends HTMLPurifier_AttrTransform {
 
-    public function transform($attr, $config, &$context) {
+    public function transform($attr, $config, $context) {
         if (!isset($attr['border'])) return $attr;
         $border_width = $this->confiscateAttr($attr, 'border');
         // some validation should happen here
diff --git a/library/HTMLPurifier/AttrTransform/EnumToCSS.php b/library/HTMLPurifier/AttrTransform/EnumToCSS.php
index 93f26157..b02fbaf6 100644
--- a/library/HTMLPurifier/AttrTransform/EnumToCSS.php
+++ b/library/HTMLPurifier/AttrTransform/EnumToCSS.php
@@ -36,7 +36,7 @@ class HTMLPurifier_AttrTransform_EnumToCSS extends HTMLPurifier_AttrTransform {
         $this->caseSensitive = (bool) $case_sensitive;
     }
     
-    public function transform($attr, $config, &$context) {
+    public function transform($attr, $config, $context) {
         
         if (!isset($attr[$this->attr])) return $attr;
         
diff --git a/library/HTMLPurifier/AttrTransform/ImgRequired.php b/library/HTMLPurifier/AttrTransform/ImgRequired.php
index 5074c3f4..7f0bdf3b 100644
--- a/library/HTMLPurifier/AttrTransform/ImgRequired.php
+++ b/library/HTMLPurifier/AttrTransform/ImgRequired.php
@@ -28,7 +28,7 @@ HTMLPurifier_ConfigSchema::define(
 class HTMLPurifier_AttrTransform_ImgRequired extends HTMLPurifier_AttrTransform
 {
     
-    public function transform($attr, $config, &$context) {
+    public function transform($attr, $config, $context) {
         
         $src = true;
         if (!isset($attr['src'])) {
diff --git a/library/HTMLPurifier/AttrTransform/ImgSpace.php b/library/HTMLPurifier/AttrTransform/ImgSpace.php
index 7fc2718d..a5cfa74c 100644
--- a/library/HTMLPurifier/AttrTransform/ImgSpace.php
+++ b/library/HTMLPurifier/AttrTransform/ImgSpace.php
@@ -20,7 +20,7 @@ class HTMLPurifier_AttrTransform_ImgSpace extends HTMLPurifier_AttrTransform {
         }
     }
     
-    public function transform($attr, $config, &$context) {
+    public function transform($attr, $config, $context) {
         
         if (!isset($attr[$this->attr])) return $attr;
         
diff --git a/library/HTMLPurifier/AttrTransform/Lang.php b/library/HTMLPurifier/AttrTransform/Lang.php
index a8e53c70..c8c86f7a 100644
--- a/library/HTMLPurifier/AttrTransform/Lang.php
+++ b/library/HTMLPurifier/AttrTransform/Lang.php
@@ -10,7 +10,7 @@ require_once 'HTMLPurifier/AttrTransform.php';
 class HTMLPurifier_AttrTransform_Lang extends HTMLPurifier_AttrTransform
 {
     
-    public function transform($attr, $config, &$context) {
+    public function transform($attr, $config, $context) {
         
         $lang     = isset($attr['lang']) ? $attr['lang'] : false;
         $xml_lang = isset($attr['xml:lang']) ? $attr['xml:lang'] : false;
diff --git a/library/HTMLPurifier/AttrTransform/Length.php b/library/HTMLPurifier/AttrTransform/Length.php
index 88ecfae5..3cff5de3 100644
--- a/library/HTMLPurifier/AttrTransform/Length.php
+++ b/library/HTMLPurifier/AttrTransform/Length.php
@@ -16,7 +16,7 @@ class HTMLPurifier_AttrTransform_Length extends HTMLPurifier_AttrTransform
         $this->cssName = $css_name ? $css_name : $name;
     }
     
-    public function transform($attr, $config, &$context) {
+    public function transform($attr, $config, $context) {
         if (!isset($attr[$this->name])) return $attr;
         $length = $this->confiscateAttr($attr, $this->name);
         if(ctype_digit($length)) $length .= 'px';
diff --git a/library/HTMLPurifier/AttrTransform/Name.php b/library/HTMLPurifier/AttrTransform/Name.php
index 6ebabf8e..d89c11a4 100644
--- a/library/HTMLPurifier/AttrTransform/Name.php
+++ b/library/HTMLPurifier/AttrTransform/Name.php
@@ -8,7 +8,7 @@ require_once 'HTMLPurifier/AttrTransform.php';
 class HTMLPurifier_AttrTransform_Name extends HTMLPurifier_AttrTransform
 {
     
-    public function transform($attr, $config, &$context) {
+    public function transform($attr, $config, $context) {
         if (!isset($attr['name'])) return $attr;
         $id = $this->confiscateAttr($attr, 'name');
         if ( isset($attr['id']))   return $attr;
diff --git a/library/HTMLPurifier/AttrValidator.php b/library/HTMLPurifier/AttrValidator.php
index e2b2a123..092cf152 100644
--- a/library/HTMLPurifier/AttrValidator.php
+++ b/library/HTMLPurifier/AttrValidator.php
@@ -18,7 +18,7 @@ class HTMLPurifier_AttrValidator
      * @param $config Instance of HTMLPurifier_Config
      * @param $context Instance of HTMLPurifier_Context
      */
-    public function validateToken(&$token, &$config, &$context) {
+    public function validateToken(&$token, &$config, $context) {
             
         $definition = $config->getHTMLDefinition();
         $e =& $context->get('ErrorCollector', true);
diff --git a/library/HTMLPurifier/ChildDef.php b/library/HTMLPurifier/ChildDef.php
index 8bb294f5..927f728d 100644
--- a/library/HTMLPurifier/ChildDef.php
+++ b/library/HTMLPurifier/ChildDef.php
@@ -48,7 +48,7 @@ class HTMLPurifier_ChildDef
      * @return bool false to remove parent node
      * @return array of replacement child tokens
      */
-    public function validateChildren($tokens_of_children, $config, &$context) {
+    public function validateChildren($tokens_of_children, $config, $context) {
         trigger_error('Call to abstract function', E_USER_ERROR);
     }
 }
diff --git a/library/HTMLPurifier/ChildDef/Chameleon.php b/library/HTMLPurifier/ChildDef/Chameleon.php
index 5da8eb39..72037c48 100644
--- a/library/HTMLPurifier/ChildDef/Chameleon.php
+++ b/library/HTMLPurifier/ChildDef/Chameleon.php
@@ -36,7 +36,7 @@ class HTMLPurifier_ChildDef_Chameleon extends HTMLPurifier_ChildDef
         $this->elements = $this->block->elements;
     }
     
-    public function validateChildren($tokens_of_children, $config, &$context) {
+    public function validateChildren($tokens_of_children, $config, $context) {
         if ($context->get('IsInline') === false) {
             return $this->block->validateChildren(
                 $tokens_of_children, $config, $context);
diff --git a/library/HTMLPurifier/ChildDef/Custom.php b/library/HTMLPurifier/ChildDef/Custom.php
index a51c3c91..2b062d0b 100644
--- a/library/HTMLPurifier/ChildDef/Custom.php
+++ b/library/HTMLPurifier/ChildDef/Custom.php
@@ -61,7 +61,7 @@ class HTMLPurifier_ChildDef_Custom extends HTMLPurifier_ChildDef
         
         $this->_pcre_regex = $reg;
     }
-    public function validateChildren($tokens_of_children, $config, &$context) {
+    public function validateChildren($tokens_of_children, $config, $context) {
         $list_of_children = '';
         $nesting = 0; // depth into the nest
         foreach ($tokens_of_children as $token) {
diff --git a/library/HTMLPurifier/ChildDef/Empty.php b/library/HTMLPurifier/ChildDef/Empty.php
index 038ab8df..e6e5b727 100644
--- a/library/HTMLPurifier/ChildDef/Empty.php
+++ b/library/HTMLPurifier/ChildDef/Empty.php
@@ -14,7 +14,7 @@ class HTMLPurifier_ChildDef_Empty extends HTMLPurifier_ChildDef
     public $allow_empty = true;
     public $type = 'empty';
     public function __construct() {}
-    public function validateChildren($tokens_of_children, $config, &$context) {
+    public function validateChildren($tokens_of_children, $config, $context) {
         return array();
     }
 }
diff --git a/library/HTMLPurifier/ChildDef/Optional.php b/library/HTMLPurifier/ChildDef/Optional.php
index 96f03a01..46cdb06a 100644
--- a/library/HTMLPurifier/ChildDef/Optional.php
+++ b/library/HTMLPurifier/ChildDef/Optional.php
@@ -13,7 +13,7 @@ class HTMLPurifier_ChildDef_Optional extends HTMLPurifier_ChildDef_Required
 {
     public $allow_empty = true;
     public $type = 'optional';
-    public function validateChildren($tokens_of_children, $config, &$context) {
+    public function validateChildren($tokens_of_children, $config, $context) {
         $result = parent::validateChildren($tokens_of_children, $config, $context);
         if ($result === false) {
             if (empty($tokens_of_children)) return true;
diff --git a/library/HTMLPurifier/ChildDef/Required.php b/library/HTMLPurifier/ChildDef/Required.php
index b563dd67..0438b440 100644
--- a/library/HTMLPurifier/ChildDef/Required.php
+++ b/library/HTMLPurifier/ChildDef/Required.php
@@ -32,7 +32,7 @@ class HTMLPurifier_ChildDef_Required extends HTMLPurifier_ChildDef
     }
     public $allow_empty = false;
     public $type = 'required';
-    public function validateChildren($tokens_of_children, $config, &$context) {
+    public function validateChildren($tokens_of_children, $config, $context) {
         // if there are no tokens, delete parent node
         if (empty($tokens_of_children)) return false;
         
diff --git a/library/HTMLPurifier/ChildDef/StrictBlockquote.php b/library/HTMLPurifier/ChildDef/StrictBlockquote.php
index 7db7d287..b018d6ed 100644
--- a/library/HTMLPurifier/ChildDef/StrictBlockquote.php
+++ b/library/HTMLPurifier/ChildDef/StrictBlockquote.php
@@ -13,7 +13,7 @@ extends HTMLPurifier_ChildDef_Required
     public $allow_empty = true;
     public $type = 'strictblockquote';
     protected $init = false;
-    public function validateChildren($tokens_of_children, $config, &$context) {
+    public function validateChildren($tokens_of_children, $config, $context) {
         
         $def = $config->getHTMLDefinition();
         if (!$this->init) {
diff --git a/library/HTMLPurifier/ChildDef/Table.php b/library/HTMLPurifier/ChildDef/Table.php
index 21072e75..dd7f6b55 100644
--- a/library/HTMLPurifier/ChildDef/Table.php
+++ b/library/HTMLPurifier/ChildDef/Table.php
@@ -12,7 +12,7 @@ class HTMLPurifier_ChildDef_Table extends HTMLPurifier_ChildDef
     public $elements = array('tr' => true, 'tbody' => true, 'thead' => true,
         'tfoot' => true, 'caption' => true, 'colgroup' => true, 'col' => true);
     public function __construct() {}
-    public function validateChildren($tokens_of_children, $config, &$context) {
+    public function validateChildren($tokens_of_children, $config, $context) {
         if (empty($tokens_of_children)) return false;
         
         // this ensures that the loop gets run one last time before closing
diff --git a/library/HTMLPurifier/Context.php b/library/HTMLPurifier/Context.php
index 655634e2..d3ca78a0 100644
--- a/library/HTMLPurifier/Context.php
+++ b/library/HTMLPurifier/Context.php
@@ -69,7 +69,7 @@ class HTMLPurifier_Context
      * Loads a series of variables from an associative array
      * @param $context_array Assoc array of variables to load
      */
-    public function loadArray(&$context_array) {
+    public function loadArray($context_array) {
         foreach ($context_array as $key => $discard) {
             $this->register($key, $context_array[$key]);
         }
diff --git a/library/HTMLPurifier/Encoder.php b/library/HTMLPurifier/Encoder.php
index af358932..47209676 100644
--- a/library/HTMLPurifier/Encoder.php
+++ b/library/HTMLPurifier/Encoder.php
@@ -309,7 +309,7 @@ class HTMLPurifier_Encoder
     /**
      * Converts a string to UTF-8 based on configuration.
      */
-    public static function convertToUTF8($str, $config, &$context) {
+    public static function convertToUTF8($str, $config, $context) {
         static $iconv = null;
         if ($iconv === null) $iconv = function_exists('iconv');
         $encoding = $config->get('Core', 'Encoding');
@@ -327,7 +327,7 @@ class HTMLPurifier_Encoder
      * @note Currently, this is a lossy conversion, with unexpressable
      *       characters being omitted.
      */
-    public static function convertFromUTF8($str, $config, &$context) {
+    public static function convertFromUTF8($str, $config, $context) {
         static $iconv = null;
         if ($iconv === null) $iconv = function_exists('iconv');
         $encoding = $config->get('Core', 'Encoding');
diff --git a/library/HTMLPurifier/ErrorCollector.php b/library/HTMLPurifier/ErrorCollector.php
index ccce883c..3c1e7fd1 100644
--- a/library/HTMLPurifier/ErrorCollector.php
+++ b/library/HTMLPurifier/ErrorCollector.php
@@ -14,7 +14,7 @@ class HTMLPurifier_ErrorCollector
     protected $generator;
     protected $context;
     
-    public function __construct(&$context) {
+    public function __construct($context) {
         $this->locale    =& $context->get('Locale');
         $this->generator =& $context->get('Generator');
         $this->context   =& $context;
diff --git a/library/HTMLPurifier/Filter.php b/library/HTMLPurifier/Filter.php
index daa39ec7..61b9b0d6 100644
--- a/library/HTMLPurifier/Filter.php
+++ b/library/HTMLPurifier/Filter.php
@@ -30,14 +30,14 @@ class HTMLPurifier_Filter
     /**
      * Pre-processor function, handles HTML before HTML Purifier 
      */
-    public function preFilter($html, $config, &$context) {
+    public function preFilter($html, $config, $context) {
         return $html;
     }
     
     /**
      * Post-processor function, handles HTML after HTML Purifier
      */
-    public function postFilter($html, $config, &$context) {
+    public function postFilter($html, $config, $context) {
         return $html;
     }
     
diff --git a/library/HTMLPurifier/Filter/ExtractStyleBlocks.php b/library/HTMLPurifier/Filter/ExtractStyleBlocks.php
index bfdd5469..112ad79f 100644
--- a/library/HTMLPurifier/Filter/ExtractStyleBlocks.php
+++ b/library/HTMLPurifier/Filter/ExtractStyleBlocks.php
@@ -42,7 +42,7 @@ class HTMLPurifier_Filter_ExtractStyleBlocks extends HTMLPurifier_Filter
      * Removes inline <style> tags from HTML, saves them for later use
      * @todo Extend to indicate non-text/css style blocks
      */
-    public function preFilter($html, $config, &$context) {
+    public function preFilter($html, $config, $context) {
         $html = preg_replace_callback('#<style(?:\s.*)?>(.+)</style>#isU', array($this, 'styleCallback'), $html);
         $style_blocks = $this->_styleMatches;
         $this->_styleMatches = array(); // reset
@@ -63,7 +63,7 @@ class HTMLPurifier_Filter_ExtractStyleBlocks extends HTMLPurifier_Filter
      * @param $context Instance of HTMLPurifier_Context
      * @return Cleaned CSS
      */
-    public function cleanCSS($css, $config, &$context) {
+    public function cleanCSS($css, $config, $context) {
         $this->_tidy->parse($css);
         $css_definition = $config->getDefinition('CSS');
         foreach ($this->_tidy->css as &$decls) {
diff --git a/library/HTMLPurifier/Filter/YouTube.php b/library/HTMLPurifier/Filter/YouTube.php
index efd8b06b..ff89b6cf 100644
--- a/library/HTMLPurifier/Filter/YouTube.php
+++ b/library/HTMLPurifier/Filter/YouTube.php
@@ -7,14 +7,14 @@ class HTMLPurifier_Filter_YouTube extends HTMLPurifier_Filter
     
     public $name = 'YouTube';
     
-    public function preFilter($html, $config, &$context) {
+    public function preFilter($html, $config, $context) {
         $pre_regex = '#<object[^>]+>.+?'.
             'http://www.youtube.com/v/([A-Za-z0-9\-_]+).+?</object>#s';
         $pre_replace = '<span class="youtube-embed">\1</span>';
         return preg_replace($pre_regex, $pre_replace, $html);
     }
     
-    public function postFilter($html, $config, &$context) {
+    public function postFilter($html, $config, $context) {
         $post_regex = '#<span class="youtube-embed">([A-Za-z0-9\-_]+)</span>#';
         $post_replace = '<object width="425" height="350" '.
             'data="http://www.youtube.com/v/\1">'.
diff --git a/library/HTMLPurifier/Generator.php b/library/HTMLPurifier/Generator.php
index 4eee5bda..b4a6d6ed 100644
--- a/library/HTMLPurifier/Generator.php
+++ b/library/HTMLPurifier/Generator.php
@@ -78,7 +78,7 @@ class HTMLPurifier_Generator
      * @param $config HTMLPurifier_Config object
      * @return Generated HTML
      */
-    public function generateFromTokens($tokens, $config, &$context) {
+    public function generateFromTokens($tokens, $config, $context) {
         $html = '';
         if (!$config) $config = HTMLPurifier_Config::createDefault();
         $this->_scriptFix   = $config->get('Output', 'CommentScriptContents');
diff --git a/library/HTMLPurifier/HTMLModule/Scripting.php b/library/HTMLPurifier/HTMLModule/Scripting.php
index 2e46d4db..1b348e70 100644
--- a/library/HTMLPurifier/HTMLModule/Scripting.php
+++ b/library/HTMLPurifier/HTMLModule/Scripting.php
@@ -12,7 +12,7 @@ INSIDE HTML PURIFIER DOCUMENTS. USE ONLY WITH TRUSTED USER INPUT!!!
  */
 class HTMLPurifier_AttrTransform_ScriptRequired extends HTMLPurifier_AttrTransform
 {
-    public function transform($attr, $config, &$context) {
+    public function transform($attr, $config, $context) {
         if (!isset($attr['type'])) {
             $attr['type'] = 'text/javascript';
         }
diff --git a/library/HTMLPurifier/IDAccumulator.php b/library/HTMLPurifier/IDAccumulator.php
index 290bd8d1..a840460d 100644
--- a/library/HTMLPurifier/IDAccumulator.php
+++ b/library/HTMLPurifier/IDAccumulator.php
@@ -26,7 +26,7 @@ class HTMLPurifier_IDAccumulator
      * @param $context Instance of HTMLPurifier_Context
      * @return Fully initialized HTMLPurifier_IDAccumulator
      */
-    public static function build($config, &$context) {
+    public static function build($config, $context) {
         $id_accumulator = new HTMLPurifier_IDAccumulator();
         $id_accumulator->load($config->get('Attr', 'IDBlacklist'));
         return $id_accumulator;
diff --git a/library/HTMLPurifier/Injector.php b/library/HTMLPurifier/Injector.php
index 7858c352..c9f9f2eb 100644
--- a/library/HTMLPurifier/Injector.php
+++ b/library/HTMLPurifier/Injector.php
@@ -64,7 +64,7 @@ abstract class HTMLPurifier_Injector
      * @param $context Instance of HTMLPurifier_Context
      * @return Boolean false if success, string of missing needed element/attribute if failure
      */
-    public function prepare($config, &$context) {
+    public function prepare($config, $context) {
         $this->htmlDefinition = $config->getHTMLDefinition();
         // perform $needed checks
         foreach ($this->needed as $element => $attributes) {
diff --git a/library/HTMLPurifier/Injector/PurifierLinkify.php b/library/HTMLPurifier/Injector/PurifierLinkify.php
index d66321c0..5d78c4a0 100644
--- a/library/HTMLPurifier/Injector/PurifierLinkify.php
+++ b/library/HTMLPurifier/Injector/PurifierLinkify.php
@@ -32,7 +32,7 @@ class HTMLPurifier_Injector_PurifierLinkify extends HTMLPurifier_Injector
     public $docURL;
     public $needed = array('a' => array('href'));
     
-    public function prepare($config, &$context) {
+    public function prepare($config, $context) {
         $this->docURL = $config->get('AutoFormatParam', 'PurifierLinkifyDocURL');
         return parent::prepare($config, $context);
     }
diff --git a/library/HTMLPurifier/Language.php b/library/HTMLPurifier/Language.php
index 266699b4..a7d10033 100644
--- a/library/HTMLPurifier/Language.php
+++ b/library/HTMLPurifier/Language.php
@@ -36,7 +36,7 @@ class HTMLPurifier_Language
      */
     protected $config, $context;
     
-    public function __construct($config, &$context) {
+    public function __construct($config, $context) {
         $this->config  = $config;
         $this->context =& $context;
     }
diff --git a/library/HTMLPurifier/LanguageFactory.php b/library/HTMLPurifier/LanguageFactory.php
index 93934ce6..2a8fdf90 100644
--- a/library/HTMLPurifier/LanguageFactory.php
+++ b/library/HTMLPurifier/LanguageFactory.php
@@ -89,7 +89,7 @@ class HTMLPurifier_LanguageFactory
      * @param $config Instance of HTMLPurifier_Config
      * @param $context Instance of HTMLPurifier_Context
      */
-    public function create($config, &$context) {
+    public function create($config, $context) {
         
         // validate language code
         $code = $this->validator->validate(
diff --git a/library/HTMLPurifier/Lexer.php b/library/HTMLPurifier/Lexer.php
index 8307a54f..51f948ca 100644
--- a/library/HTMLPurifier/Lexer.php
+++ b/library/HTMLPurifier/Lexer.php
@@ -263,7 +263,7 @@ class HTMLPurifier_Lexer
      * @param $string String HTML.
      * @return HTMLPurifier_Token array representation of HTML.
      */
-    public function tokenizeHTML($string, $config, &$context) {
+    public function tokenizeHTML($string, $config, $context) {
         trigger_error('Call to abstract class', E_USER_ERROR);
     }
     
@@ -311,7 +311,7 @@ class HTMLPurifier_Lexer
      * encoding, extracting bits, and other good stuff.
      * @todo Consider making protected
      */
-    public function normalize($html, $config, &$context) {
+    public function normalize($html, $config, $context) {
         
         // extract body from document if applicable
         if ($config->get('Core', 'ConvertDocumentToFragment')) {
diff --git a/library/HTMLPurifier/Lexer/DOMLex.php b/library/HTMLPurifier/Lexer/DOMLex.php
index 6f6f0183..d3cc9023 100644
--- a/library/HTMLPurifier/Lexer/DOMLex.php
+++ b/library/HTMLPurifier/Lexer/DOMLex.php
@@ -38,7 +38,7 @@ class HTMLPurifier_Lexer_DOMLex extends HTMLPurifier_Lexer
         $this->factory = new HTMLPurifier_TokenFactory();
     }
     
-    public function tokenizeHTML($html, $config, &$context) {
+    public function tokenizeHTML($html, $config, $context) {
         
         $html = $this->normalize($html, $config, $context);
         
@@ -173,7 +173,7 @@ class HTMLPurifier_Lexer_DOMLex extends HTMLPurifier_Lexer
     /**
      * Wraps an HTML fragment in the necessary HTML
      */
-    protected function wrapHTML($html, $config, &$context) {
+    protected function wrapHTML($html, $config, $context) {
         $def = $config->getDefinition('HTML');
         $ret = '';
         
diff --git a/library/HTMLPurifier/Lexer/DirectLex.php b/library/HTMLPurifier/Lexer/DirectLex.php
index a6aff4ae..af333015 100644
--- a/library/HTMLPurifier/Lexer/DirectLex.php
+++ b/library/HTMLPurifier/Lexer/DirectLex.php
@@ -42,7 +42,7 @@ class HTMLPurifier_Lexer_DirectLex extends HTMLPurifier_Lexer
         return $matches[1] . htmlspecialchars($matches[2], ENT_COMPAT, 'UTF-8') . $matches[3];
     }
     
-    public function tokenizeHTML($html, $config, &$context) {
+    public function tokenizeHTML($html, $config, $context) {
         
         // special normalization for script tags without any armor
         // our "armor" heurstic is a < sign any number of whitespaces after
@@ -340,7 +340,7 @@ class HTMLPurifier_Lexer_DirectLex extends HTMLPurifier_Lexer
      * @param $string Inside of tag excluding name.
      * @returns Assoc array of attributes.
      */
-    public function parseAttributeString($string, $config, &$context) {
+    public function parseAttributeString($string, $config, $context) {
         $string = (string) $string; // quick typecast
         
         if ($string == '') return array(); // no attributes
diff --git a/library/HTMLPurifier/Lexer/PEARSax3.php b/library/HTMLPurifier/Lexer/PEARSax3.php
index bb46a9d4..c359a613 100644
--- a/library/HTMLPurifier/Lexer/PEARSax3.php
+++ b/library/HTMLPurifier/Lexer/PEARSax3.php
@@ -30,7 +30,7 @@ class HTMLPurifier_Lexer_PEARSax3 extends HTMLPurifier_Lexer
      */
     protected $tokens = array();
     
-    public function tokenizeHTML($string, $config, &$context) {
+    public function tokenizeHTML($string, $config, $context) {
         
         $this->tokens = array();
         
diff --git a/library/HTMLPurifier/Lexer/PH5P.php b/library/HTMLPurifier/Lexer/PH5P.php
index b6762379..b43d145f 100644
--- a/library/HTMLPurifier/Lexer/PH5P.php
+++ b/library/HTMLPurifier/Lexer/PH5P.php
@@ -10,7 +10,7 @@ require_once 'HTMLPurifier/Lexer/DOMLex.php';
 
 class HTMLPurifier_Lexer_PH5P extends HTMLPurifier_Lexer_DOMLex {
     
-    public function tokenizeHTML($html, $config, &$context) {
+    public function tokenizeHTML($html, $config, $context) {
         $html = $this->normalize($html, $config, $context);
         $html = $this->wrapHTML( $html, $config, $context);
         $parser = new HTML5($html);
diff --git a/library/HTMLPurifier/Strategy.php b/library/HTMLPurifier/Strategy.php
index 10db0b51..974f6857 100644
--- a/library/HTMLPurifier/Strategy.php
+++ b/library/HTMLPurifier/Strategy.php
@@ -24,7 +24,7 @@ abstract class HTMLPurifier_Strategy
      * @param $config Configuration options
      * @returns Processed array of token objects.
      */
-    abstract public function execute($tokens, $config, &$context);
+    abstract public function execute($tokens, $config, $context);
     
 }
 
diff --git a/library/HTMLPurifier/Strategy/Composite.php b/library/HTMLPurifier/Strategy/Composite.php
index a047509d..46ae25b7 100644
--- a/library/HTMLPurifier/Strategy/Composite.php
+++ b/library/HTMLPurifier/Strategy/Composite.php
@@ -16,7 +16,7 @@ abstract class HTMLPurifier_Strategy_Composite extends HTMLPurifier_Strategy
     
     abstract public function __construct();
     
-    public function execute($tokens, $config, &$context) {
+    public function execute($tokens, $config, $context) {
         foreach ($this->strategies as $strategy) {
             $tokens = $strategy->execute($tokens, $config, $context);
         }
diff --git a/library/HTMLPurifier/Strategy/FixNesting.php b/library/HTMLPurifier/Strategy/FixNesting.php
index b0593521..14e7ab83 100644
--- a/library/HTMLPurifier/Strategy/FixNesting.php
+++ b/library/HTMLPurifier/Strategy/FixNesting.php
@@ -34,7 +34,7 @@ require_once 'HTMLPurifier/HTMLDefinition.php';
 class HTMLPurifier_Strategy_FixNesting extends HTMLPurifier_Strategy
 {
     
-    public function execute($tokens, $config, &$context) {
+    public function execute($tokens, $config, $context) {
         //####################################################################//
         // Pre-processing
         
diff --git a/library/HTMLPurifier/Strategy/MakeWellFormed.php b/library/HTMLPurifier/Strategy/MakeWellFormed.php
index 763f5fad..81ad42e6 100644
--- a/library/HTMLPurifier/Strategy/MakeWellFormed.php
+++ b/library/HTMLPurifier/Strategy/MakeWellFormed.php
@@ -31,7 +31,7 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy
     protected $inputTokens, $inputIndex, $outputTokens, $currentNesting,
         $currentInjector, $injectors;
     
-    public function execute($tokens, $config, &$context) {
+    public function execute($tokens, $config, $context) {
         
         $definition = $config->getHTMLDefinition();
         
@@ -280,7 +280,7 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy
         return $result;
     }
     
-    function processToken($token, $config, &$context) {
+    function processToken($token, $config, $context) {
         if (is_array($token)) {
             // the original token was overloaded by an injector, time
             // to some fancy acrobatics
diff --git a/library/HTMLPurifier/Strategy/RemoveForeignElements.php b/library/HTMLPurifier/Strategy/RemoveForeignElements.php
index 59566819..8c39f9a9 100644
--- a/library/HTMLPurifier/Strategy/RemoveForeignElements.php
+++ b/library/HTMLPurifier/Strategy/RemoveForeignElements.php
@@ -55,7 +55,7 @@ HTMLPurifier_ConfigSchema::define(
 class HTMLPurifier_Strategy_RemoveForeignElements extends HTMLPurifier_Strategy
 {
     
-    public function execute($tokens, $config, &$context) {
+    public function execute($tokens, $config, $context) {
         $definition = $config->getHTMLDefinition();
         $generator = new HTMLPurifier_Generator();
         $result = array();
diff --git a/library/HTMLPurifier/Strategy/ValidateAttributes.php b/library/HTMLPurifier/Strategy/ValidateAttributes.php
index 569adda4..8cb42fbb 100644
--- a/library/HTMLPurifier/Strategy/ValidateAttributes.php
+++ b/library/HTMLPurifier/Strategy/ValidateAttributes.php
@@ -13,7 +13,7 @@ require_once 'HTMLPurifier/AttrValidator.php';
 class HTMLPurifier_Strategy_ValidateAttributes extends HTMLPurifier_Strategy
 {
     
-    public function execute($tokens, $config, &$context) {
+    public function execute($tokens, $config, $context) {
         
         // setup validator
         $validator = new HTMLPurifier_AttrValidator();
diff --git a/library/HTMLPurifier/TagTransform.php b/library/HTMLPurifier/TagTransform.php
index cbfbea0d..34413dd3 100644
--- a/library/HTMLPurifier/TagTransform.php
+++ b/library/HTMLPurifier/TagTransform.php
@@ -19,7 +19,7 @@ abstract class HTMLPurifier_TagTransform
      * @param $config Mandatory HTMLPurifier_Config object
      * @param $context Mandatory HTMLPurifier_Context object
      */
-    abstract public function transform($tag, $config, &$context);
+    abstract public function transform($tag, $config, $context);
     
     /**
      * Prepends CSS properties to the style attribute, creating the
diff --git a/library/HTMLPurifier/TagTransform/Font.php b/library/HTMLPurifier/TagTransform/Font.php
index 9ec99b4c..607199ed 100644
--- a/library/HTMLPurifier/TagTransform/Font.php
+++ b/library/HTMLPurifier/TagTransform/Font.php
@@ -36,7 +36,7 @@ class HTMLPurifier_TagTransform_Font extends HTMLPurifier_TagTransform
         '+4' => '300%'
     );
     
-    public function transform($tag, $config, &$context) {
+    public function transform($tag, $config, $context) {
         
         if ($tag->type == 'end') {
             $new_tag = $tag->copy();
diff --git a/library/HTMLPurifier/TagTransform/Simple.php b/library/HTMLPurifier/TagTransform/Simple.php
index 242752ec..d1e52ba6 100644
--- a/library/HTMLPurifier/TagTransform/Simple.php
+++ b/library/HTMLPurifier/TagTransform/Simple.php
@@ -21,7 +21,7 @@ class HTMLPurifier_TagTransform_Simple extends HTMLPurifier_TagTransform
         $this->style = $style;
     }
     
-    public function transform($tag, $config, &$context) {
+    public function transform($tag, $config, $context) {
         $new_tag = $tag->copy();
         $new_tag->name = $this->transform_to;
         if (!is_null($this->style) &&
diff --git a/library/HTMLPurifier/URI.php b/library/HTMLPurifier/URI.php
index fef9ce33..10f6c19c 100644
--- a/library/HTMLPurifier/URI.php
+++ b/library/HTMLPurifier/URI.php
@@ -30,8 +30,8 @@ class HTMLPurifier_URI
      * @param $context Instance of HTMLPurifier_Context
      * @return Scheme object appropriate for validating this URI
      */
-    public function getSchemeObj($config, &$context) {
-        $registry =& HTMLPurifier_URISchemeRegistry::instance();
+    public function getSchemeObj($config, $context) {
+        $registry = HTMLPurifier_URISchemeRegistry::instance();
         if ($this->scheme !== null) {
             $scheme_obj = $registry->getScheme($this->scheme, $config, $context);
             if (!$scheme_obj) return false; // invalid scheme, clean it out
@@ -57,7 +57,7 @@ class HTMLPurifier_URI
      * @param $context Instance of HTMLPurifier_Context
      * @return True if validation/filtering succeeds, false if failure
      */
-    public function validate($config, &$context) {
+    public function validate($config, $context) {
         
         // validate host
         if (!is_null($this->host)) {
diff --git a/library/HTMLPurifier/URIDefinition.php b/library/HTMLPurifier/URIDefinition.php
index f9a7ddd8..f6b434cf 100644
--- a/library/HTMLPurifier/URIDefinition.php
+++ b/library/HTMLPurifier/URIDefinition.php
@@ -134,7 +134,7 @@ class HTMLPurifier_URIDefinition extends HTMLPurifier_Definition
         if (is_null($this->defaultScheme)) $this->defaultScheme = $config->get('URI', 'DefaultScheme');
     }
     
-    public function filter(&$uri, $config, &$context) {
+    public function filter(&$uri, $config, $context) {
         foreach ($this->filters as $name => $x) {
             $result = $this->filters[$name]->filter($uri, $config, $context);
             if (!$result) return false;
diff --git a/library/HTMLPurifier/URIFilter.php b/library/HTMLPurifier/URIFilter.php
index 5c316ab6..b832a4ae 100644
--- a/library/HTMLPurifier/URIFilter.php
+++ b/library/HTMLPurifier/URIFilter.php
@@ -28,11 +28,11 @@ abstract class HTMLPurifier_URIFilter
      * Filter a URI object
      * @param &$uri Reference to URI object
      * @param $config Instance of HTMLPurifier_Config
-     * @param &$context Instance of HTMLPurifier_Context
+     * @param $context Instance of HTMLPurifier_Context
      * @return bool Whether or not to continue processing: false indicates
      *         URL is no good, true indicates continue processing. Note that
      *         all changes are committed directly on the URI object
      */
-    abstract public function filter(&$uri, $config, &$context);
+    abstract public function filter(&$uri, $config, $context);
     
 }
diff --git a/library/HTMLPurifier/URIFilter/DisableExternal.php b/library/HTMLPurifier/URIFilter/DisableExternal.php
index 8eb6bd9c..1ba02b6d 100644
--- a/library/HTMLPurifier/URIFilter/DisableExternal.php
+++ b/library/HTMLPurifier/URIFilter/DisableExternal.php
@@ -20,7 +20,7 @@ class HTMLPurifier_URIFilter_DisableExternal extends HTMLPurifier_URIFilter
         $our_host = $config->get('URI', 'Host');
         if ($our_host !== null) $this->ourHostParts = array_reverse(explode('.', $our_host));
     }
-    public function filter(&$uri, $config, &$context) {
+    public function filter(&$uri, $config, $context) {
         if (is_null($uri->host)) return true;
         if ($this->ourHostParts === false) return false;
         $host_parts = array_reverse(explode('.', $uri->host));
diff --git a/library/HTMLPurifier/URIFilter/DisableExternalResources.php b/library/HTMLPurifier/URIFilter/DisableExternalResources.php
index 489d20eb..da3bdcc4 100644
--- a/library/HTMLPurifier/URIFilter/DisableExternalResources.php
+++ b/library/HTMLPurifier/URIFilter/DisableExternalResources.php
@@ -18,7 +18,7 @@ HTMLPurifier_ConfigSchema::define(
 class HTMLPurifier_URIFilter_DisableExternalResources extends HTMLPurifier_URIFilter_DisableExternal
 {
     public $name = 'DisableExternalResources';
-    public function filter(&$uri, $config, &$context) {
+    public function filter(&$uri, $config, $context) {
         if (!$context->get('EmbeddedURI', true)) return true;
         return parent::filter($uri, $config, $context);
     }
diff --git a/library/HTMLPurifier/URIFilter/HostBlacklist.php b/library/HTMLPurifier/URIFilter/HostBlacklist.php
index a7dbfecb..914afc73 100644
--- a/library/HTMLPurifier/URIFilter/HostBlacklist.php
+++ b/library/HTMLPurifier/URIFilter/HostBlacklist.php
@@ -17,7 +17,7 @@ class HTMLPurifier_URIFilter_HostBlacklist extends HTMLPurifier_URIFilter
     public function prepare($config) {
         $this->blacklist = $config->get('URI', 'HostBlacklist');
     }
-    public function filter(&$uri, $config, &$context) {
+    public function filter(&$uri, $config, $context) {
         foreach($this->blacklist as $blacklisted_host_fragment) {
             if (strpos($uri->host, $blacklisted_host_fragment) !== false) {
                 return false;
diff --git a/library/HTMLPurifier/URIFilter/MakeAbsolute.php b/library/HTMLPurifier/URIFilter/MakeAbsolute.php
index bfb4c592..ea0d1540 100644
--- a/library/HTMLPurifier/URIFilter/MakeAbsolute.php
+++ b/library/HTMLPurifier/URIFilter/MakeAbsolute.php
@@ -33,7 +33,7 @@ class HTMLPurifier_URIFilter_MakeAbsolute extends HTMLPurifier_URIFilter
         $stack = $this->_collapseStack($stack); // do pre-parsing
         $this->basePathStack = $stack;
     }
-    public function filter(&$uri, $config, &$context) {
+    public function filter(&$uri, $config, $context) {
         if (is_null($this->base)) return true; // abort early
         if (
             $uri->path === '' && is_null($uri->scheme) &&
diff --git a/library/HTMLPurifier/URIScheme.php b/library/HTMLPurifier/URIScheme.php
index 8921e871..fada3870 100644
--- a/library/HTMLPurifier/URIScheme.php
+++ b/library/HTMLPurifier/URIScheme.php
@@ -32,7 +32,7 @@ class HTMLPurifier_URIScheme
      * @param $context HTMLPurifier_Context object
      * @return Bool success or failure
      */
-    public function validate(&$uri, $config, &$context) {
+    public function validate(&$uri, $config, $context) {
         if ($this->default_port == $uri->port) $uri->port = null;
         return true;
     }
diff --git a/library/HTMLPurifier/URIScheme/ftp.php b/library/HTMLPurifier/URIScheme/ftp.php
index 9309e60d..4396a1d3 100644
--- a/library/HTMLPurifier/URIScheme/ftp.php
+++ b/library/HTMLPurifier/URIScheme/ftp.php
@@ -11,7 +11,7 @@ class HTMLPurifier_URIScheme_ftp extends HTMLPurifier_URIScheme {
     public $browsable = true; // usually
     public $hierarchical = true;
     
-    public function validate(&$uri, $config, &$context) {
+    public function validate(&$uri, $config, $context) {
         parent::validate($uri, $config, $context);
         $uri->query    = null;
         
diff --git a/library/HTMLPurifier/URIScheme/http.php b/library/HTMLPurifier/URIScheme/http.php
index e164195f..1bc21338 100644
--- a/library/HTMLPurifier/URIScheme/http.php
+++ b/library/HTMLPurifier/URIScheme/http.php
@@ -11,7 +11,7 @@ class HTMLPurifier_URIScheme_http extends HTMLPurifier_URIScheme {
     public $browsable = true;
     public $hierarchical = true;
     
-    public function validate(&$uri, $config, &$context) {
+    public function validate(&$uri, $config, $context) {
         parent::validate($uri, $config, $context);
         $uri->userinfo = null;
         return true;
diff --git a/library/HTMLPurifier/URIScheme/mailto.php b/library/HTMLPurifier/URIScheme/mailto.php
index f81e5afa..e2e459fe 100644
--- a/library/HTMLPurifier/URIScheme/mailto.php
+++ b/library/HTMLPurifier/URIScheme/mailto.php
@@ -15,7 +15,7 @@ class HTMLPurifier_URIScheme_mailto extends HTMLPurifier_URIScheme {
     
     public $browsable = false;
     
-    public function validate(&$uri, $config, &$context) {
+    public function validate(&$uri, $config, $context) {
         parent::validate($uri, $config, $context);
         $uri->userinfo = null;
         $uri->host     = null;
diff --git a/library/HTMLPurifier/URIScheme/news.php b/library/HTMLPurifier/URIScheme/news.php
index b13d9531..1763f4f8 100644
--- a/library/HTMLPurifier/URIScheme/news.php
+++ b/library/HTMLPurifier/URIScheme/news.php
@@ -9,7 +9,7 @@ class HTMLPurifier_URIScheme_news extends HTMLPurifier_URIScheme {
     
     public $browsable = false;
     
-    public function validate(&$uri, $config, &$context) {
+    public function validate(&$uri, $config, $context) {
         parent::validate($uri, $config, $context);
         $uri->userinfo = null;
         $uri->host     = null;
diff --git a/library/HTMLPurifier/URIScheme/nntp.php b/library/HTMLPurifier/URIScheme/nntp.php
index ad9cfba2..e358f4de 100644
--- a/library/HTMLPurifier/URIScheme/nntp.php
+++ b/library/HTMLPurifier/URIScheme/nntp.php
@@ -10,7 +10,7 @@ class HTMLPurifier_URIScheme_nntp extends HTMLPurifier_URIScheme {
     public $default_port = 119;
     public $browsable = false;
     
-    public function validate(&$uri, $config, &$context) {
+    public function validate(&$uri, $config, $context) {
         parent::validate($uri, $config, $context);
         $uri->userinfo = null;
         $uri->query    = null;
diff --git a/library/HTMLPurifier/URISchemeRegistry.php b/library/HTMLPurifier/URISchemeRegistry.php
index fd8f65e2..4b983b30 100644
--- a/library/HTMLPurifier/URISchemeRegistry.php
+++ b/library/HTMLPurifier/URISchemeRegistry.php
@@ -43,7 +43,7 @@ class HTMLPurifier_URISchemeRegistry
      * @note Pass a registry object $prototype with a compatible interface and
      *       the function will copy it and return it all further times.
      */
-    public static function &instance($prototype = null) {
+    public static function instance($prototype = null) {
         static $instance = null;
         if ($prototype !== null) {
             $instance = $prototype;
@@ -64,7 +64,7 @@ class HTMLPurifier_URISchemeRegistry
      * @param $config HTMLPurifier_Config object
      * @param $config HTMLPurifier_Context object
      */
-    public function &getScheme($scheme, $config, &$context) {
+    public function getScheme($scheme, $config, $context) {
         if (!$config) $config = HTMLPurifier_Config::createDefault();
         $null = null; // for the sake of passing by reference
         
@@ -90,8 +90,8 @@ class HTMLPurifier_URISchemeRegistry
      * @param $scheme Scheme name
      * @param $scheme_obj HTMLPurifier_URIScheme object
      */
-    public function register($scheme, &$scheme_obj) {
-        $this->schemes[$scheme] =& $scheme_obj;
+    public function register($scheme, $scheme_obj) {
+        $this->schemes[$scheme] = $scheme_obj;
     }
     
 }
diff --git a/tests/HTMLPurifier/URITest.php b/tests/HTMLPurifier/URITest.php
index 6424e73b..c15fbed7 100644
--- a/tests/HTMLPurifier/URITest.php
+++ b/tests/HTMLPurifier/URITest.php
@@ -23,21 +23,21 @@ class HTMLPurifier_URITest extends HTMLPurifier_URIHarness
         $this->oldRegistry = HTMLPurifier_URISchemeRegistry::instance();
         generate_mock_once('HTMLPurifier_URIScheme');
         generate_mock_once('HTMLPurifier_URISchemeRegistry');
-        $registry =& HTMLPurifier_URISchemeRegistry::instance(
+        $registry = HTMLPurifier_URISchemeRegistry::instance(
           new HTMLPurifier_URISchemeRegistryMock()
         );
         return $registry;
     }
     
-    function &setUpSchemeMock($name) {
-        $registry =& $this->setUpSchemeRegistryMock();
+    function setUpSchemeMock($name) {
+        $registry = $this->setUpSchemeRegistryMock();
         $scheme_mock = new HTMLPurifier_URISchemeMock();
         $registry->setReturnValue('getScheme', $scheme_mock, array($name, '*', '*'));
         return $scheme_mock;
     }
     
     function setUpNoValidSchemes() {
-        $registry =& $this->setUpSchemeRegistryMock();
+        $registry = $this->setUpSchemeRegistryMock();
         $registry->setReturnValue('getScheme', false, array('*', '*', '*'));
     }
     
@@ -46,7 +46,7 @@ class HTMLPurifier_URITest extends HTMLPurifier_URIHarness
     }
     
     function test_getSchemeObj() {
-        $scheme_mock =& $this->setUpSchemeMock('http');
+        $scheme_mock = $this->setUpSchemeMock('http');
         
         $uri = $this->createURI('http:');
         $scheme_obj = $uri->getSchemeObj($this->config, $this->context);
@@ -68,7 +68,7 @@ class HTMLPurifier_URITest extends HTMLPurifier_URIHarness
     function test_getSchemaObj_defaultScheme() {
         $scheme = 'foobar';
         
-        $scheme_mock =& $this->setUpSchemeMock($scheme);
+        $scheme_mock = $this->setUpSchemeMock($scheme);
         $this->config->set('URI', 'DefaultScheme', $scheme);
         
         $uri = $this->createURI('hmm');
diff --git a/tests/multitest.php b/tests/multitest.php
index ede78197..2b07011b 100644
--- a/tests/multitest.php
+++ b/tests/multitest.php
@@ -1,5 +1,14 @@
 <?php
 
+/** @file
+ * Multiple PHP Versions test
+ * 
+ * This file tests HTML Purifier in all versions of PHP. It requires a
+ * script called phpv that takes an extra argument, $version, before
+ * the filename, is required. Contact me if you'd like to set up a
+ * similar script.
+ */
+
 $versions_to_test = array(
     'FLUSH',
     '5.0.0',