function valida_us(form)
{
  if (form.email.value.indexOf('@', 0) == -1 ||
      form.email.value.indexOf('.', 0) == -1 )
  { alert("Invalid e-mail"); form.email.focus(); return; }

  if (form.email.value != form.email2.value )
   { alert("Different e-mail"); form.email.focus(); return; }

  form.submit();
}

function valida_es(form)
{
  if (form.email.value.indexOf('@', 0) == -1 ||
      form.email.value.indexOf('.', 0) == -1 )
  { alert("Dirección de e-mail inválida"); form.email.focus(); return; }

  if (form.email.value != form.email2.value )
   { alert("Dirección de e-mail diferente"); form.email.focus(); return; }

  form.submit();
}