diff --git a/actionpack/lib/action_controller/assertions/response_assertions.rb b/actionpack/lib/action_controller/assertions/response_assertions.rb
index c0b78552f2..0811920e4a 100644
--- a/actionpack/lib/action_controller/assertions/response_assertions.rb
+++ b/actionpack/lib/action_controller/assertions/response_assertions.rb
@@ -70,14 +70,14 @@ module ActionController
 
               if value.respond_to?(:[]) && value['controller']
                 if key == :actual && value['controller'].first != '/' && !value['controller'].include?('/')
-                  value['controller'] = ActionController::Routing.controller_relative_to(value['controller'], @controller.class.controller_path)
+                  new_controller_path = ActionController::Routing.controller_relative_to(value['controller'], @controller.class.controller_path)
+                  value['controller'] = new_controller_path if value['controller'] != new_controller_path && ActionController::Routing.possible_controllers.include?(new_controller_path)
                 end
                 value['controller'] = value['controller'][1..-1] if value['controller'].first == '/' # strip leading hash
               end
               url[key] = value
             end
 
-
             @response_diff = url[:expected].diff(url[:actual]) if url[:actual]
             msg = build_message(message, "response is not a redirection to all of the options supplied (redirection is <?>), difference: <?>",
                                 url[:actual], @response_diff)
diff --git a/actionpack/test/controller/action_pack_assertions_test.rb b/actionpack/test/controller/action_pack_assertions_test.rb
index 5f5e1dca26..21930aa061 100644
--- a/actionpack/test/controller/action_pack_assertions_test.rb
+++ b/actionpack/test/controller/action_pack_assertions_test.rb
@@ -139,6 +139,10 @@ module Admin
     def redirect_to_fellow_controller
       redirect_to :controller => 'user'
     end
+    
+    def redirect_to_top_level_named_route
+      redirect_to top_level_url(:id => "foo")
+    end
   end
 end
 
@@ -150,15 +154,20 @@ end
 # production environment
 ActionPackAssertionsController.template_root = File.dirname(__FILE__) + "/../fixtures/"
 
-
 # a test case to exercise the new capabilities TestRequest & TestResponse
 class ActionPackAssertionsControllerTest < Test::Unit::TestCase
   # let's get this party started
   def setup
+    ActionController::Routing::Routes.reload
+    ActionController::Routing.use_controllers!(%w(action_pack_assertions admin/inner_module content admin/user))
     @controller = ActionPackAssertionsController.new
     @request, @response = ActionController::TestRequest.new, ActionController::TestResponse.new
   end
 
+  def teardown
+    ActionController::Routing::Routes.reload
+  end
+
   # -- assertion-based testing ------------------------------------------------
 
   def test_assert_tag_and_url_for
@@ -294,6 +303,19 @@ class ActionPackAssertionsControllerTest < Test::Unit::TestCase
       assert_redirected_to admin_inner_module_path
     end
   end
+  
+  def test_assert_redirected_to_top_level_named_route_from_nested_controller
+    with_routing do |set|
+      set.draw do |map|
+        map.top_level '/action_pack_assertions/:id', :controller => 'action_pack_assertions', :action => 'index'
+        map.connect   ':controller/:action/:id'
+      end
+      @controller = Admin::InnerModuleController.new
+      process :redirect_to_top_level_named_route
+      # passes -> assert_redirected_to "http://test.host/action_pack_assertions/foo"
+      assert_redirected_to "/action_pack_assertions/foo"
+    end
+  end
 
   # test the flash-based assertions with something is in the flash
   def test_flash_assertions_full
diff --git a/actionpack/test/controller/test_test.rb b/actionpack/test/controller/test_test.rb
index bc2651c281..2b0086c5f4 100644
--- a/actionpack/test/controller/test_test.rb
+++ b/actionpack/test/controller/test_test.rb
@@ -86,7 +86,7 @@ HTML
     @request    = ActionController::TestRequest.new
     @response   = ActionController::TestResponse.new
     ActionController::Routing::Routes.reload
-    ActionController::Routing.use_controllers! %w(content admin/user)
+    ActionController::Routing.use_controllers! %w(content admin/user test_test/test)
   end
 
   def teardown