diff --git a/library/HTMLPurifier/ElementDef.php b/library/HTMLPurifier/ElementDef.php
index 7c37d956..3a167ba4 100644
--- a/library/HTMLPurifier/ElementDef.php
+++ b/library/HTMLPurifier/ElementDef.php
@@ -93,7 +93,17 @@ class HTMLPurifier_ElementDef
     function mergeIn($def) {
         
         // later keys takes precedence
-        foreach($def->attr                  as $k => $v) $this->attr[$k]                = $v;
+        foreach($def->attr as $k => $v) {
+            if ($k == 0) {
+                // merge in the includes
+                // sorry, no way to override an include
+                foreach ($v as $v2) {
+                    $def->attr[0][] = $v2;
+                }
+                continue;
+            }
+            $this->attr[$k] = $v;
+        }
         foreach($def->attr_transform_pre    as $k => $v) $this->attr_transform_pre[$k]  = $v;
         foreach($def->attr_transform_post   as $k => $v) $this->attr_transform_post[$k] = $v;
         foreach($def->auto_close            as $k => $v) $this->auto_close[$k]          = $v;
diff --git a/library/HTMLPurifier/HTMLDefinition.php b/library/HTMLPurifier/HTMLDefinition.php
index 21b8599e..7e7ac0b2 100644
--- a/library/HTMLPurifier/HTMLDefinition.php
+++ b/library/HTMLPurifier/HTMLDefinition.php
@@ -36,6 +36,7 @@ require_once 'HTMLPurifier/HTMLModule/StyleAttribute.php';
 
 // compat modules
 require_once 'HTMLPurifier/HTMLModule/TransformToStrict.php';
+require_once 'HTMLPurifier/HTMLModule/Legacy.php';
 
 HTMLPurifier_ConfigSchema::define(
     'HTML', 'EnableAttrID', false, 'bool',
@@ -256,6 +257,7 @@ class HTMLPurifier_HTMLDefinition
         $this->modules['StyleAttribute']= new HTMLPurifier_HTMLModule_StyleAttribute();
         
         $this->modules['TransformToStrict'] = new HTMLPurifier_HTMLModule_TransformToStrict($config);
+        if (!$this->strict) $this->modules['Legacy'] = new HTMLPurifier_HTMLModule_Legacy($config);
         
         $this->attr_types       = new HTMLPurifier_AttrTypes();
         $this->attr_collections = new HTMLPurifier_AttrCollections();
@@ -393,42 +395,6 @@ class HTMLPurifier_HTMLDefinition
      */
     function setupCompat($config) {
         
-        // convenience for compat
-        $e_Inline = new HTMLPurifier_ChildDef_Optional(
-                        $this->info_content_sets['Inline'] +
-                        array('#PCDATA' => true));
-        
-        // blockquote alt child def, implement in Legacy
-        if (!$this->strict) {
-            $this->info['blockquote']->child =
-                new HTMLPurifier_ChildDef_Optional(
-                    $this->info_content_sets['Flow'] +
-                    array('#PCDATA' => true));
-        }
-        
-        // deprecated element definitions, implement in Legacy
-        if (!$this->strict) {
-            $this->info['u'] =
-            $this->info['s'] =
-            $this->info['strike'] = new HTMLPurifier_ElementDef();
-            $this->info['u']->child =
-            $this->info['s']->child =
-            $this->info['strike']->child = $e_Inline;
-            $this->info['u']->descendants_are_inline =
-            $this->info['s']->descendants_are_inline =
-            $this->info['strike']->descendants_are_inline = true;
-        }
-        
-        // changed content model for loose, implement in Legacy
-        if ($this->strict) {
-            $this->info['address']->child = $e_Inline;
-        } else {
-            $this->info['address']->child =
-                new HTMLPurifier_ChildDef_Optional(
-                $this->info_content_sets['Inline'] + 
-                array('#PCDATA' => true, 'p' => true));
-        }
-        
         // deprecated config setting, implement in DisableURI module
         if ($config->get('Attr', 'DisableURI')) {
             $this->info['a']->attr['href'] =
@@ -440,12 +406,6 @@ class HTMLPurifier_HTMLDefinition
             $this->info['img']->attr['src'] = null;
         }
         
-        // deprecated attributes implementations, implement in Legacy
-        if (!$this->strict) {
-            $this->info['li']->attr['value'] = new HTMLPurifier_AttrDef_Integer();
-            $this->info['ol']->attr['start'] = new HTMLPurifier_AttrDef_Integer();
-        }
-        
         // setup allowed elements, SubtractiveWhitelist module
         $allowed_elements = $config->get('HTML', 'AllowedElements');
         if (is_array($allowed_elements)) {
diff --git a/library/HTMLPurifier/HTMLModule/Legacy.php b/library/HTMLPurifier/HTMLModule/Legacy.php
index 92674cf7..0a7111ba 100644
--- a/library/HTMLPurifier/HTMLModule/Legacy.php
+++ b/library/HTMLPurifier/HTMLModule/Legacy.php
@@ -17,7 +17,40 @@
 class HTMLPurifier_HTMLModule_Legacy extends HTMLPurifier_HTMLModule
 {
     
-    // unimplemented
+    // incomplete
+    
+    var $elements = array('u', 's', 'strike');
+    var $non_standalone_elements = array('li', 'ol', 'address', 'blockquote');
+    
+    function HTMLPurifier_HTMLModule_Legacy() {
+        // setup new elements
+        foreach ($this->elements as $name) {
+            $this->info[$name] = new HTMLPurifier_ElementDef();
+            // for u, s, strike, as more elements get added, add
+            // conditionals as necessary
+            $this->info[$name]->content_model = 'Inline | #PCDATA';
+            $this->info[$name]->content_model_type = 'optional';
+            $this->info[$name]->attr[0] = array('Common');
+        }
+        
+        // setup modifications to old elements
+        foreach ($this->non_standalone_elements as $name) {
+            $this->info[$name] = new HTMLPurifier_ElementDef();
+            $this->info[$name]->standalone = false;
+        }
+        
+        $this->info['li']->attr['value'] = new HTMLPurifier_AttrDef_Integer();
+        $this->info['ol']->attr['start'] = new HTMLPurifier_AttrDef_Integer();
+        
+        $this->info['address']->content_model = 'Inline | #PCDATA | p';
+        $this->info['address']->content_model_type = 'optional';
+        $this->info['address']->child = false;
+        
+        $this->info['blockquote']->content_model = 'Flow | #PCDATA';
+        $this->info['blockquote']->content_model_type = 'optional';
+        $this->info['blockquote']->child = false;
+        
+    }
     
 }
 
diff --git a/tests/HTMLPurifier/Test.php b/tests/HTMLPurifier/Test.php
index daa39f53..3fa54173 100644
--- a/tests/HTMLPurifier/Test.php
+++ b/tests/HTMLPurifier/Test.php
@@ -83,6 +83,20 @@ class HTMLPurifier_Test extends UnitTestCase
         
     }
     
+    function testEnableAttrID() {
+        
+        $this->purifier = new HTMLPurifier();
+        
+        $this->assertPurification(
+            '<span id="moon">foobar</span>',
+            '<span>foobar</span>'
+        );
+        
+        $this->purifier = new HTMLPurifier(array('HTML.EnableAttrID' => true));
+        $this->assertPurification('<span id="moon">foobar</span>');
+        
+    }
+    
 }
 
 ?>
\ No newline at end of file