public function save(Application_Model_Friend $friend)
 {
     $data = array('id' => $friend->getId(), 'user_id' => $friend->getUserId(), 'friend_user_id' => $friend->getFriendUserId(), 'confirmed' => $friend->getConfirmed());
     if (null === ($id = $friend->getId())) {
         unset($data['id']);
         return $this->getDbTable()->insert($data);
     } else {
         $this->getDbTable()->update($data, array('id = ?' => $id));
     }
 }