diff --git a/actionpack/CHANGELOG b/actionpack/CHANGELOG
index 040d1162ad468..9797f244104a1 100644
--- a/actionpack/CHANGELOG
+++ b/actionpack/CHANGELOG
@@ -1,5 +1,10 @@
 *SVN*
 
+* Added that render :xml will try to call to_xml if it can [DHH]. Makes these work:
+
+    render :xml => post
+    render :xml => comments
+
 * Added :location option to render so that the common pattern of rendering a response after creating a new resource is now a 1-liner [DHH]
 
     render :xml => post.to_xml, :status => :created, :location => post_url(post)
diff --git a/actionpack/lib/action_controller/base.rb b/actionpack/lib/action_controller/base.rb
index c0c91a3ac9b01..c1c9e57342d94 100755
--- a/actionpack/lib/action_controller/base.rb
+++ b/actionpack/lib/action_controller/base.rb
@@ -879,7 +879,7 @@ def render_javascript(javascript, status = nil, append_response = true) #:nodoc:
 
       def render_xml(xml, status = nil) #:nodoc:
         response.content_type = Mime::XML
-        render_text(xml, status)
+        render_text(xml.respond_to?(:to_xml) ? xml.to_xml : xml, status)
       end
 
       def render_json(json, callback = nil, status = nil) #:nodoc:
diff --git a/actionpack/test/controller/new_render_test.rb b/actionpack/test/controller/new_render_test.rb
index 0765772e061c5..18a32f6e30a16 100644
--- a/actionpack/test/controller/new_render_test.rb
+++ b/actionpack/test/controller/new_render_test.rb
@@ -258,6 +258,20 @@ def head_with_status_code_first
     head :forbidden, :x_custom_header => "something"
   end
 
+  def render_with_location
+    render :xml => "<hello/>", :location => "http://example.com", :status => 201
+  end
+
+  def render_with_to_xml
+    to_xmlable = Class.new do
+      def to_xml
+        "<i-am-xml/>"
+      end
+    end.new
+    
+    render :xml => to_xmlable
+  end
+
   helper NewRenderTestHelper
   helper do 
     def rjs_helper_method(value)
@@ -742,4 +756,14 @@ def test_head_with_status_code_first
     assert_equal "something", @response.headers["X-Custom-Header"]
     assert_response :forbidden
   end
-end
+
+  def test_rendering_with_location_should_set_header
+    get :render_with_location
+    assert_equal "http://example.com", @response.headers["Location"]
+  end
+  
+  def test_rendering_xml_should_call_to_xml_if_possible
+    get :render_with_to_xml
+    assert_equal "<i-am-xml/>", @response.body
+  end
+end
\ No newline at end of file
diff --git a/actionpack/test/controller/render_test.rb b/actionpack/test/controller/render_test.rb
index eb23ed0c5b614..d51af51454593 100644
--- a/actionpack/test/controller/render_test.rb
+++ b/actionpack/test/controller/render_test.rb
@@ -73,10 +73,6 @@ def heading
     head :ok
   end
 
-  def location
-    render :xml => "<hello/>", :location => "http://example.com", :status => 201
-  end
-
   def greeting
     # let's just rely on the template
   end
@@ -372,11 +368,6 @@ def test_should_render_formatted_html_erb_template_with_faulty_accepts_header
     assert_equal '<test>passed formatted html erb</test>', @response.body
   end
 
-  def test_rendering_with_location_should_set_header
-    get :location
-    assert_equal "http://example.com", @response.headers["Location"]
-  end
-
 
   protected
     def assert_deprecated_render(&block)