rem: try { trans = Components.classes["@mozilla.org/widget/transferable;1"].createInstance(Components.interfaces.nsITransferable); trans.addDataFlavor("text/x-moz-address"); } catch (ex) { return; } 
add: var trans = Components.classes["@mozilla.org/widget/transferable;1"] .createInstance(Components.interfaces.nsITransferable); trans.addDataFlavor("text/x-moz-address"); 
context: function DragAddressOverTargetControl(event){  var dragSession = gDragService.getCurrentSession();  if (!dragSession.isDataFlavorSupported("text/x-moz-address"))     return;  try {    trans = Components.classes["@mozilla.org/widget/transferable;1"].createInstance(Components.interfaces.nsITransferable);    trans.addDataFlavor("text/x-moz-address");  }  catch (ex) {    return;  }  var canDrop = true;  for ( var i = 0; i < dragSession.numDropItems; ++i )  {    dragSession.getData ( trans, i );    var dataObj = new Object();    var bestFlavor = new Object();    var len = new Object();    try    {      trans.getAnyTransferData ( bestFlavor, dataObj, len );    }    catch (ex)    {      canDrop = false;      break;    }  }  dragSession.canDrop = canDrop;}
meta: 8395	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/8395/94b8a218de513b4d838d354dbe98ab9bea2221d7/abDragDrop.js/buggy/mailnews/addrbook/resources/content/abDragDrop.js