Statu bar is still running

i have a button, when onclick it will call this function by opening a dhtmlxwindows

function ToDelete(lngNo) {		

	var add = "WaitingList.asp?RequestType=DeleteObj&No=" + lngNo;

	dhxWins = new dhtmlXWindows();
	win = dhxWins.createWindow("w3", 0, 0, 0, 0);
	win.attachURL(add );   				

After that it will go into the function required and do something, then it will return The window is closed but the status bar is still running. May i know what is the cause? Thanks!

Please provide the complete demo and details about browser.