/**
  * Returns instance of Tinebase_Config
  *
  * @return Tinebase_Config
  */
 public static function getInstance()
 {
     if (self::$_instance === NULL) {
         self::$_instance = new self();
     }
     return self::$_instance;
 }
 public function __construct()
 {
     $this->_config = RequestTracker_Config::getInstance();
     $this->_connect();
 }