function popup( url )
{
  winStats='toolbar=no,location=no,directories=no,menubar=no,'
  winStats+='scrollbars=1,width=820,height=615'
  if (navigator.appName.indexOf("Microsoft")>=0) {
     winStats+=',left=' + (screen.width-600)/2 +',top=25'
   }else{
     winStats+=',screenX=' + (screen.width-600)/2 + ',screenY=25'
   }
  floater=window.open( url, "name", winStats)
}