diff -u b/core/includes/bootstrap.inc b/core/includes/bootstrap.inc
--- b/core/includes/bootstrap.inc
+++ b/core/includes/bootstrap.inc
@@ -1021,7 +1021,7 @@
   chdir(DRUPAL_ROOT);
 
   try {
-    foreach ($callbacks as $key => $callbacks) {
+    foreach ($callbacks as $key => $callback) {
       call_user_func_array($callback['callback'], $callback['arguments']);
     }
   }