diff -r 322d0feea350 -r 89ef5ed3c48b src/cm/media/js/client/c_layout.js
--- a/src/cm/media/js/client/c_layout.js	Mon Jul 15 15:25:58 2013 +0200
+++ b/src/cm/media/js/client/c_layout.js	Tue Jul 16 14:29:46 2013 +0200
@@ -50,8 +50,8 @@
   },
   
   setLeftColumnWidth : function (colWidth) {
-    CY.get('#contentcolumn').setStyle('marginLeft', colWidth + 'px');
-    CY.get('#leftcolumn').setStyle('width', colWidth + 'px');
+    CY.one('#contentcolumn').setStyle('marginLeft', colWidth + 'px');
+    CY.one('#leftcolumn').setStyle('width', colWidth + 'px');
   },
   parentInterfaceUnfreeze : function() {
     if (this.isInFrame())