function submitenter_simple(myfield,e)
{
 var keycode;
 if (window.event) keycode = window.event.keyCode;
 else if (e) keycode = e.which;
 else return true;
 if (keycode == 13)
 {
  busca_simple();
  return false;
 }
 else
 {
  //alert("no se ha dado al enter");
  return true;
 }
}

function submitenter_complex(myfield,e)
{
 var keycode;
 if (window.event) keycode = window.event.keyCode;
 else if (e) keycode = e.which;
 else return true;
 if (keycode == 13)
 {
  document.getElementById('search_advaced').submit();;
  return false;
 }
 else
 {
  //alert("no se ha dado al enter");
  return true;
 }
}