Создание модуля рейтинга статей из mod_zooitem - ZOO 2.х

Fatal error: Uncaught YDatabase::queryObjectList failed. (Unknown column 'c.value' in 'field list' SQL=SELECT a.*, AVG(c.value) FROM jos_zoo_item AS a WHERE a.application_id = 2 AND a.access <= 0 AND a.state = 1 AND a.type = 'online-shops-catalog' AND (a.publish_up = '0000-00-00 00:00:00' OR a.publish_up <= '2010-09-23 07:30:23') AND (a.publish_down = '0000-00-00 00:00:00' OR a.publish_down >= '2010-09-23 07:30:23') ORDER BY a.hits DESC LIMIT 0, 4) thrown in C:\wamp\www\sitename\administrator\components\com_zoo\framework\database.php  on line 83

// set query options
		$conditions = 
		     "a.application_id = ".(int) $app->id
			." AND a.access <= ".(int) $access_id
			." AND a.state = 1"		
			." AND a.type = '?'"		
			." AND (a.publish_up = ".$null." OR a.publish_up <= ".$now.")"
			." AND (a.publish_down = ".$null." OR a.publish_down >= ".$now.")";

		$options = array(
			'select' => 'a.*',
			'from' => ZOO_TABLE_ITEM.' AS a',
			'conditions' => array($conditions, $type),
			'order' => self::getOrder($ordering),
			'limit' => $limit);

		return $table->all($options);
	}
	
	public static function getOrder($order) {

		$orders = array(
			'date'   => 'a.created ASC',
			'rdate'  => 'a.created DESC',
			'alpha'  => 'a.name ASC',
			'ralpha' => 'a.name DESC',
			'hits'   => 'a.hits DESC',
			'rhits'  => 'a.hits ASC',
			'random' => 'RAND()');

		return isset($orders[$order])? $orders[$order] : '';
	}