ilunabar.loadEvent(function () {
  $("boton1").onmouseover = function() {
    $("boton1").writeAttribute({"src":"/pub/img/boton1_hover_es.png"});
  }

  $("boton1").onmouseout = function() {
    $("boton1").writeAttribute({"src":"/pub/img/boton1_es.png"});
  }
});