function openwin(url,winame,winheight,winwidth)
 {
 // Default sizes for window
  if (winheight==null) winheight='500';
  if (winwidth==null) winwidth='400';

 window.open(url,winame,'toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=2,resizable=2,width='+winwidth+',height='+winheight);
 }