add: aDragAction.action = Components.interfaces.nsIDragService.DRAGDROP_ACTION_MOVE; 
context:   onDragStart: function (aEvent, aXferData, aDragAction) {    var documentId = gToolboxDocument.documentElement.id;        var item = aEvent.target;    while (item && item.localName != "toolbarpaletteitem")      item = item.parentNode;        item.setAttribute("dragactive", "true");        aXferData.data = new TransferDataSet();    var data = new TransferData();    data.addDataForFlavour("text/toolbarwrapper-id/"+documentId, item.firstChild.id);    aXferData.data.push(data);  }
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/2c344292db7c2f7e0a9d5a385b0a3ba6bcc83b9b/customizeToolbar.js/buggy/toolkit/content/customizeToolbar.js