Author: Gunnar Wolf <gwolf@gwolf.org>
Origin: vendor,  https://drupal.org/node/2245331#comment-8699683
Last-Update: 2014-04-24
Applied-Upstream: yes
Description: Drupal version 7.27 introduced a regression on AJAX calls
 on IE8.
 .
 The patch has been added upstream and will be included in the next release.

Index: drupal7/misc/ajax.js
===================================================================
--- drupal7.orig/misc/ajax.js	2014-04-24 13:22:02.742818243 -0500
+++ drupal7/misc/ajax.js	2014-04-24 13:29:26.591028802 -0500
@@ -622,7 +622,7 @@
    * Command to update a form's build ID.
    */
   updateBuildId: function(ajax, response, status) {
-    $('input[name="form_build_id"][value="' + response.old + '"]').val(response.new);
+    $('input[name="form_build_id"][value="' + response['old'] + '"]').val(response['new']);
   }
 };
 
