window.addEvent('domready', function(){
  var btEnviar = $('botEnviar');
  if (btEnviar){
    btEnviar.addEvent('click', submit_form);
  }
});

function submit_form(e){
  e = new Event(e).stop();
  if ('' != $('msg').value){
    this.className = 'mc_button_wait';
    this.removeEvent('click', submit_form);
    this.parentNode.submit();
  }
};