rem: DNDUtils.checkCanDrop("OutlinerBuilder/column-remove"); 
add: DNDUtils.checkCanDrop("TreeBuilder/column-remove"); 
context:   onDragOverTarget: function(aBox, aEvent)  {    DNDUtils.checkCanDrop("OutlinerBuilder/column-remove");  },
meta: 5872	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/5872/d38a0937d9c93a0a9d913e2ac781e4328bb8cc73/inTreeBuilder.js/buggy/extensions/inspector/resources/content/jsutil/xul/inTreeBuilder.js