function AbreVentana(pagina, nombre, ancho, alto, scroll,resiz) {
   var winl = (screen.width - ancho) / 2;
   var wint = (screen.height - alto) / 2;
   winprops = 'height='+alto+',width='+ancho+',top='+wint+',left='+winl+',scrollbars='+scroll+',resizable='+resiz
   win = window.open(pagina, '', winprops)
   if (parseInt(navigator.appVersion) >= 4) { win.focus(); }
}

function abreFeria(pagina){
   window.open("http://"+pagina)	
}