protected function _redirectReferer($defaultUrl = null)
 {
     if ($this->getRequest()->isPost()) {
         $data = $this->getRequest()->getPost();
         if (isset($data['filter_param_name']) && isset($data['filter_param_value'])) {
             $refererUrl = $this->_getRefererUrl();
             if (empty($refererUrl)) {
                 $refererUrl = Mage::helper('adminhtml')->getUrl();
             } else {
                 // Update filter param value in referer URL, as it may contain unvalidated filters
                 $urlParts = explode('?', $refererUrl);
                 $paramRegex = '/' . preg_quote($data['filter_param_name'], '#') . '/.*?/';
                 $refererUrl = preg_replace('#' . $paramRegex . '#', '/', $urlParts[0]);
                 $refererUrl .= (substr($refererUrl, -1) != '/' ? '/' : '') . $data['filter_param_name'] . '/' . $data['filter_param_value'] . '/';
                 if (count($urlParts) > 1) {
                     $refererUrl .= '?' . $urlParts[1];
                 }
             }
             $this->getResponse()->setRedirect($refererUrl);
             return;
         }
     }
     parent::_redirectReferer($defaultUrl = null);
 }