function popupWindow(url, width, height, scroll) {
  if (width=='') width = 100;
  if (height=='') height = 100;
  if (scroll=='') scroll = 'no';
  var param = 'toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars='+scroll+',resizable=yes,copyhistory=no,width='+width+',height='+height+',screenX=150,screenY=150,top=150,left=150';
  window.open(url,'popupWindow',param)
}