单击YII1后，验证码不会更改

I need change captcha image when I click on it, the captcha with form located in CJuiDialog.Also form loaded via ajax In view I set:

 <?php $this->widget('CCaptcha', array('clickableImage' => true,'showRefreshButton'=>false,'captchaAction'=>'/site/captcha')); ?>

But when I click on an image it not change.Tell me please what I do wrong?

Just add id in widget:

   <?php $this->widget('CCaptcha', array('id'=>'captahca_id','clickableImage' => true,'showRefreshButton'=>false,'captchaAction'=>'captcha')); ?>