protected function uninstallCMSNavItems(Plugin $plugin)
    {
        $dto = new DTO(array('PluginID' => $plugin->PluginID));
        $navitems = $this->CMSNavItemService->findAll($dto)->getResults();

        rsort($navitems);

        foreach ($navitems as $navitem) {
            $this->CMSNavItemService->delete($navitem->Slug);
        }
    }