diff --git a/actionpack/CHANGELOG.md b/actionpack/CHANGELOG.md
index e827f935c3539..6940bd45a0d1d 100644
--- a/actionpack/CHANGELOG.md
+++ b/actionpack/CHANGELOG.md
@@ -1,5 +1,7 @@
 ## Rails 4.0.0 (unreleased) ##
 
+*   JSONP now uses mimetype application/javascript instead of application/json *omjokine*
+
 *   Allow to lazy load `default_form_builder` by passing a `String` instead of a constant. *Piotr Sarnacki*
 
 *   Session arguments passed to `process` calls in functional tests are now merged into
diff --git a/actionpack/test/controller/render_json_test.rb b/actionpack/test/controller/render_json_test.rb
index 3be70ab84f6f6..7c0a6bd67e021 100644
--- a/actionpack/test/controller/render_json_test.rb
+++ b/actionpack/test/controller/render_json_test.rb
@@ -102,7 +102,7 @@ def test_render_json_with_status
   def test_render_json_with_callback
     get :render_json_hello_world_with_callback
     assert_equal 'alert({"hello":"world"})', @response.body
-    assert_equal 'application/javascript', @response.content_type
+    assert_equal 'text/javascript', @response.content_type
   end
 
   def test_render_json_with_custom_content_type