pagina=null;
function apriPopup(url,w,h){
	x=screen.width/2-w/2;
	y=screen.height/2-h/2;
	if (pagina != null)
		pagina.close();
	pagina=window.open(url,"","fullscreen=no,status=no,toolbar=no,scrollbars=yes,width="+w+",height="+h+",top="+y+",left="+x);
}