public function attachLogger($logger, $config = array())
    {
        $identifier = $this->getIdentifier($logger);

        if (!$this->__queue->hasIdentifier($identifier))
        {
            $logger = $this->getObject($identifier, $config);

            if (!($logger instanceof ComActivitiesActivityLoggerInterface))
            {
                throw new UnexpectedValueException(
                    "Logger $identifier does not implement ComActivitiesActivityLoggerInterface"
                );
            }

            $this->__queue->enqueue($logger, self::PRIORITY_NORMAL);
        }

        return $this;
    }