static public function factory($config = array()) {
        if (is_string($config)) {
            // Assume $config is a filename
            $filename = $config;
            $config = array(
                'timestampFormat' => 'Y-m-d',
                array(
                    'writerName' => 'Stream',
                    'writerParams' => array(
                        'stream' => self::_getLoggingDirectory() . DIRECTORY_SEPARATOR . $filename
                    )
                )
            );
        }
        return parent::factory($config);
    }