var frmviewvr=new Object;
if(document.layers)
  frmviewvr.name='a';
 else
  frmviewvr=null;
function frmview(url, wdth, hght, sb)
  {
   if(document.layers)
     {
      if(frmviewvr.name=='view')
        frmviewvr.close();
     }
    else
     {
      if(frmviewvr!=null)
        {
         frmviewvr.close();
         frmviewvr=null;
        }
     }
   frmviewvr=window.open(url, 'frmview', 'channelmode=0,toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars='+sb+'0,resizeable=0,width='+wdth+',height='+hght+',left=50,top=60');
  }