function popup(url,w,h,opts) {
  if(!w)w=900;
  if(!h)h=600;
  var sw=800,sh=572;
  if (window.screen) {
    sw=screen.availWidth;
    sh=screen.availHeight;
  }
  sw-=15;
  sh-=50;
  if (w>sw) w=sw;
  if (h>sh) h=sh;
  var t=190;
  var l=sw-w;
  if (l<0) l=0;
  if (t+h>sh) t=sh-h;
  var id="w"+w+"h"+h;
  if (opts){var i=opts.indexOf("id=");if(i>=0){var j=opts.indexOf(",",i);if(j<0)j=opts.length;id=opts.substring(i+3,j);}}
  var i=url.indexOf("/",7);
  var exturl=url.indexOf("http:")!=-1&&url.substring(0,i)!=location.href.substring(0,i);
  if (exturl||!window.focus) {
    id=new Date();
    id=id.getTime();
  }
  var parm3="alwaysRaised=1,dependent=no,directories=yes,hotkeys=yes,width="+w+",height="+h+",location=yes,menubar=yes,resizable=yes,scrollbars=yes,status=yes,titlebar=yes,toolbar=yes,left="+l+",top="+t;
  var pw=window.open(url,(exturl?'':'pop_')+id,parm3);
  if(pw&&pw.focus)pw.focus()
}