function popup(str,w,h)
{

 winz = window.open(str,'popup','scrollbars=1,resizable=1,width='+w+',height='+h+',status=no,location=no,toolbar=0');
 wr= (screen.width / 2)-(w/2);
 tr= (screen.height / 2)-(h/2);
 winz.moveTo(wr,tr);

}

function openTarget (form, features, windowName)
{
  if (!windowName)
    windowName = 'formTarget' + (new Date().getTime());
  form.target = windowName;
  open ('', windowName, features);
}