call to undefined method Request::getParam ???

Question

Fatal error: Call to undefined method Request::getParam() in C:\wamp\www\Admin\corporate\for-upload\activecollab\application\modules\system\controllers\CompaniesController.class.php on line 219

in controller class I've written

$this->request->getParam('is_owner');

and in request i've passed

    $router->map('people_companies_add_owner', 'people/add-owner-company/is_owner','null', array('controller' => 'companies', 'action' => 'add_owner','is_owner'=>'true'));

urgent help is needed thnx