diff --git a/actionpack/CHANGELOG b/actionpack/CHANGELOG
index 28eef311fd9c2cafd079785c67b5ff46af442ba9..c68355254841006ff544de3a3ba733e704694ef0 100644
--- a/actionpack/CHANGELOG
+++ b/actionpack/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Update html-scanner to handle CDATA sections better. Closes #2970. [Jamis Buck]
+
 * Don't put flash in session if sessions are disabled.  [Jeremy Kemper]
 
 * Strip out trailing &_= for raw post bodies. Closes #2868. [Sam Stephenson]
diff --git a/actionpack/lib/action_controller/vendor/html-scanner/html/node.rb b/actionpack/lib/action_controller/vendor/html-scanner/html/node.rb
index 4f02e2d4212a21ae3b125acbfe24d29e30ffd969..fb961570c426c696c3d0ec65aa03a397edece760 100644
--- a/actionpack/lib/action_controller/vendor/html-scanner/html/node.rb
+++ b/actionpack/lib/action_controller/vendor/html-scanner/html/node.rb
@@ -150,6 +150,11 @@ def parse(parent, line, pos, content, strict=true)
             end
           end
 
+          if scanner.skip(/!\[CDATA\[/)
+            scanner.scan_until(/\]\]>/)
+            return CDATA.new(parent, line, pos, scanner.pre_match)
+          end
+          
           closing = ( scanner.scan(/\//) ? :close : nil )
           return Text.new(parent, line, pos, content) unless name = scanner.scan(/[\w:]+/)
           name.downcase!
@@ -256,6 +261,14 @@ def ==(node)
       content == node.content
     end
   end
+  
+  # A CDATA node is simply a text node with a specialized way of displaying
+  # itself.
+  class CDATA < Text
+    def to_s
+      "<![CDATA[#{super}]>"
+    end
+  end
 
   # A Tag is any node that represents markup. It may be an opening tag, a
   # closing tag, or a self-closing tag. It has a name, and may have a hash of
diff --git a/actionpack/lib/action_controller/vendor/html-scanner/html/tokenizer.rb b/actionpack/lib/action_controller/vendor/html-scanner/html/tokenizer.rb
index ce9d3b280085b927743de5703e5d6b415b0f9de3..b950e846284bb41047263a584f82feed009c842a 100644
--- a/actionpack/lib/action_controller/vendor/html-scanner/html/tokenizer.rb
+++ b/actionpack/lib/action_controller/vendor/html-scanner/html/tokenizer.rb
@@ -52,6 +52,9 @@ def scan_tag
         if @scanner.scan(/!--/) # comment
           tag << @scanner.matched
           tag << (@scanner.scan_until(/--\s*>/) || @scanner.scan_until(/\Z/))
+        elsif @scanner.scan(/!\[CDATA\[/)
+          tag << @scanner.matched
+          tag << @scanner.scan_until(/\]\]>/)
         elsif @scanner.scan(/!/) # doctype
           tag << @scanner.matched
           tag << consume_quoted_regions