rem: return (gTransactionMgr.numberOfUndoItems > 0); 
add: return getTransactionMgr().canUndo(); 
context: function canUndo() {    return (gTransactionMgr.numberOfUndoItems > 0);}
meta: 8395	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/8395/8f557b6620a7ffd0ae2bbc6b245ea6cb9b7a0fff/calendar-item-editing.js/buggy/calendar/base/content/calendar-item-editing.js