public function filterByEmail($email = null, $comparison = null)
    {
        if (null === $comparison) {
            if (is_array($email)) {
                $comparison = Criteria::IN;
            } elseif (preg_match('/[\%\*]/', $email)) {
                $email = str_replace('*', '%', $email);
                $comparison = Criteria::LIKE;
            }
        }

        return $this->addUsingAlias(CustomerPeer::EMAIL, $email, $comparison);
    }