script LANGUAGE="JavaScript">
function pop(vurl,vheight,vwidth,vleft,vtop) {
cadena="win";
numero=Math.random()*1000;
numero=parseInt(numero);
ancho=vwidth;
alto=vheight;
vleft=(window.screen.width/2)-(ancho/2);
vtop=(window.screen.availHeight/2)-(alto/2);
//vleft = (screen.availWidth - vheight)/2;
//vtop = (screen.availHeight - vwidth)/2;
window.open(vurl,cadena+numero,"scrollbars=no,height="+vheight+",width="+vwidth+",left="+vleft+",top="+vtop);
}