function popup(mylink, windowname)
{ 
var winleft = (screen.width - 500) / 2; 
var winUp = (screen.height - 400) / 2; 

if (! window.focus)return true; 
	var href; 
	if(typeof(mylink) == 'string') 
		href=mylink; 
	else 
		href=mylink.href; 
		window.open(href, windowname, 'top='+((screen.height - 400) / 2)+',left='+((screen.width - 500) / 2)+'+,toolbar=0 status=1,resizable=0,Width=500,height=400,scrollbars=1'); return false;
}