gistfile1.txt

-- Works on Page.php (inside Page_Controller)
    public function getViewer($action) {
        $viewer = parent::getViewer($action);
        $this->extend('updateViewer', $action, $viewer);
        return $viewer;
    }


-- Doesnt work on on Page_Controller extension !
    public function getViewer($action) {
        $viewer = $this->owner->parentClass()->getViewer($action);
        $this->owner->extend('updateViewer', $action, $viewer);
        return $viewer;
    }