rem: EnableMenuItem(menuID, (numSelected > 0)); 
add: var folderResource = GetSelectedFolderResource(); var enableMenuItem = numSelected > 0;  if (folderResource) { var msgFolder = folderResource.QueryInterface(Components.interfaces.nsIMsgFolder); enableMenuItem = enableMenuItem && msgFolder && msgFolder.canDeleteMessages; } EnableMenuItem(menuID, enableMenuItem); 
context: function SetupMoveMenuItem(menuID, numSelected, isNewsgroup, forceHide){  ShowMenuItem(menuID, !isNewsgroup && !forceHide);  EnableMenuItem(menuID, (numSelected > 0));}
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/01d7eb012bb62529182550f7c8774a8a6596b425/mailContextMenus.js/buggy/mailnews/base/resources/content/mailContextMenus.js