function open_window(sivu, param, lev, kor)
  {
    new_window = window.open(sivu,param,'left=100,top=10,alwaysRaised=YES,toolbar=NO,location=NO,directories=NO,status=NO,menubar=NO,scrollbars=YES,resizable=NO,copyhistory=NO,width='+lev+',height='+kor+'');
    new_window.focus();
  }
// error handling
   function stopError()
     {
	    return true;
     }
   window.onerror = stopError;