Index: modules/system/system-behavior.css
===================================================================
RCS file: /cvs/drupal/drupal/modules/system/system-behavior.css,v
retrieving revision 1.1
diff -u -p -r1.1 system-behavior.css
--- modules/system/system-behavior.css	7 Jan 2010 07:41:46 -0000	1.1
+++ modules/system/system-behavior.css	8 Jan 2010 03:56:36 -0000
@@ -156,7 +156,7 @@ div.tree-child-horizontal {
   border-radius: 3px;
   -moz-border-radius: 3px;
   -webkit-border-radius: 3px;
-  background: #ccc;
+  background: #ccc  url(../../misc/progress_undeterminate.gif);
   border: 1px solid #666;
   margin: 0 0.2em;
 }