diff --git a/library/HTMLPurifier/Injector/AutoParagraph.php b/library/HTMLPurifier/Injector/AutoParagraph.php
index 24ca9d5e..6e0a6a3e 100644
--- a/library/HTMLPurifier/Injector/AutoParagraph.php
+++ b/library/HTMLPurifier/Injector/AutoParagraph.php
@@ -166,7 +166,14 @@ class HTMLPurifier_Injector_AutoParagraph extends HTMLPurifier_Injector
         $needs_start = false;
         $needs_end   = false;
         
-        for ($i = 0, $c = count($raw_paragraphs); $i < $c; $i++) {
+        $c = count($raw_paragraphs);
+        if ($c == 1) {
+            // there were no double-newlines, abort quickly
+            $result[] = new HTMLPurifier_Token_Text($data);
+            return;
+        }
+        
+        for ($i = 0; $i < $c; $i++) {
             $par = $raw_paragraphs[$i];
             if (trim($par) !== '') {
                 $paragraphs[] = $par;
diff --git a/tests/HTMLPurifier/Injector/AutoParagraphTest.php b/tests/HTMLPurifier/Injector/AutoParagraphTest.php
index 441be0de..0f0b5e5e 100644
--- a/tests/HTMLPurifier/Injector/AutoParagraphTest.php
+++ b/tests/HTMLPurifier/Injector/AutoParagraphTest.php
@@ -261,6 +261,11 @@ Par1
 '<div><div>asdf</div><p><b>asdf</b></p></div>'
         );
         
+        $this->assertResult(
+'<b>One</b> <i>Two</i>',
+'<p><b>One</b> <i>Two</i></p>'
+        );
+        
     }
     
     function testInlineRootNode() {