protected function _normalizeBaseFieldConfiguration(&$config) {
        $bf_config = (array)$config['baseField'];
        $nbf_config = array();
        $defaults = array(
            'type' => 'text',
            'format' => null
        );
        foreach ($bf_config as $bf) {
            $bf = is_string($bf) ? array('column' => $bf) : $bf;
            $bf = array_merge($defaults, $bf);
            $nbf_config[] = $bf;
        }
        $config['baseField'] = $nbf_config;
    }