public function readExtendedMetadata($meta, array &$config)
    {
        $tableName = $meta->getTableName();
        if (!isset($GLOBALS['TL_DCA'][$tableName])) {
            $this->loadDataContainer($tableName);
        }

        $dca    = (array) $GLOBALS['TL_DCA'][$tableName];
        $fields = (array) $dca['fields'];
        foreach ($fields as $fieldName => $field) {
            if (isset($field['field']['timestampable']['on'])) {
                $config[$field['field']['timestampable']['on']][] = $fieldName;
            }
        }
    }