Email-validator doesn't work

I'm generating my models from YAML. The email validator is correctly parsed into the model, but it doesn't work. If I try to insert 'a' or something that is not valid, I don't get any error at all and the row is inserted. See attachments for models.

$user = new AppUser();
$user->name = 'Testuser';
$user->password = sha1('lala');
$user->email = 'a';
$user->role = 'ADMIN';
$user->save();