function popup(mylink, windowname)
{
if (! window.focus)return true;
var href;
if (typeof(mylink) == 'string')
   href=mylink;
else
   href=mylink.href;
   
var leftPos = (screen.width - 250) / 2, topPos = (screen.height - 100) / 2;
window.open(href, windowname, 'width=480,height=250,left='+leftPos+',top='+topPos+',scrollbars=no');
return false;
}