private function _createUserFriendlyPassword($base, $length)
    {
        // empty placeholder
        $password = '';

        // length for userfriendly must be multiple of two
        if ($length % 2 > 0) {
            throw new Doozr_Exception('Length of userfriendly-password must be a multiple of two!');
        }

        // build password
        for ($i = 0; $i < $length; ++$i) {
            // every 2nd char is of type consonant
            if ((($i + 1) % 2) != 0) {
                $password .= $this->getRandomCharacter($base['default']);
            } else {
                $password .= $this->getRandomCharacter($base['special']);
            }
        }

        // return password
        return $password;
    }