public function login()
	{
		if($this->_identity===null)
		{
			$this->_identity=new UserIdentity('yiier',$this->password);
			$this->_identity->authenticate();
		}
		if($this->_identity->errorCode===UserIdentity::ERROR_NONE)
		{
			Yii::app()->user->login($this->_identity);
			return true;
		}
		else
			return false;
	}