RegistrationModel::validateUserEmail PHP Method

    public static function validateUserEmail($user_email, $user_email_repeat)
    {
        if (empty($user_email)) {
            Session::add('feedback_negative', Text::get('FEEDBACK_EMAIL_FIELD_EMPTY'));
            return false;
        }
        if ($user_email !== $user_email_repeat) {
            Session::add('feedback_negative', Text::get('FEEDBACK_EMAIL_REPEAT_WRONG'));
            return false;
        }
        // validate the email with PHP's internal filter
        // side-fact: Max length seems to be 254 chars
        // @see http://stackoverflow.com/questions/386294/what-is-the-maximum-length-of-a-valid-email-address
        if (!filter_var($user_email, FILTER_VALIDATE_EMAIL)) {
            Session::add('feedback_negative', Text::get('FEEDBACK_EMAIL_DOES_NOT_FIT_PATTERN'));
            return false;
        }
        return true;
    }