function openpopupres(popurl,l,a)
{
//var popurl="http://site.com/page.htm"

var altura=window.screen.height;
var largura=window.screen.width;
var topo=(altura/2)-192; 
var esquerda=(largura/2)-262;
var definicoes="toolbar=no,location=no,status=no,menubar=no,scrollbars=no,resizable=no, width="+parseInt(l+30)+", height="+parseInt(a+30)+",top="+ topo + ",left=" + esquerda;
//var definicoes='toolbar=no,location=no,status=no,menubar=no,scrollbars=no,resizable=no,width=590,height=300,top='+ topo + ',left=' + esquerda;


winpops=window.open(popurl,"",definicoes);

}