Yii Framework Captcha Conflict With Beforeaction() Function

I have app in Yii and i extend all classes from some base controller and i have these code in it :


protected function beforeAction($action)

    {

        $this->setglobalvariable();

        return parent::beforeAction($action);

    }

as i just understand , these code prevent the Captcha to show , because when i delete it , the captcha shows up ! the captcha function is :


public function actions()

    {

        return array(

            // captcha action renders the CAPTCHA image displayed on the contact page

            'captcha'=>array(

                'class'=>'CCaptchaAction',

                'backColor'=>0xFFFFFF,

                'minLength'=>2,

                'maxLength'=>3,

                'width'=>60,

            ),

            // page action renders "static" pages stored under 'protected/views/site/pages'

            // They can be accessed via: index.php?r=site/page&view=FileName

            'page'=>array(

                'class'=>'CViewAction',

            ),

        );

    }

So how could i use beforeAction and captcha in same time ?