zend delete

 public function indexAction()
     {
        
      $guestbook = new Application_Model_GuestbookMapper();
      $this->view->entries = $guestbook->fetchAll();
        
        //echo $this->_getParam('name');
        
        //Zend_Debug::dump($this->_request->getParams());
        
      $Application_Model_Guestbook = new Application_Model_Guestbook();       
      $Application_Model_Guestbook->setComment('exemple');
      $Application_Model_Guestbook->setEmail('exemple');
        
        //Zend_Debug::dump( $Application_Model_Guestbook);
               
      if($this->_request->isPost()) 
      
      {          
      $Application_Model_Guestbook = new Application_Model_Guestbook();
      $Application_Model_Guestbook->setComment('');
      $Application_Model_Guestbook->setEmail('');          
      $guestbook->save($Application_Model_Guestbook);
      }    
                      
     //   $Application_Model_DbTable_Guestbook = new Application_Model_DbTable_Guestbook();
     
     //   $Application_Model_DbTable_Guestbook->insert(array('comment'=>'toto'));
            
       
       if ($this->getRequest()->isGet())         
       {
       $request = $this->getRequest();     
       $id = $request->getParam('id', 0);     
       // $where = $this->quoteInto('id = ?', $id);
       $where = $id;   
       echo $id;   
       $Application_Model_DbTable_Guestbook = new Application_Model_DbTable_Guestbook();            
       $Application_Model_DbTable_Guestbook->delete($where);                          
       } 
         
       }