public function getRoleChildren($role) {
        $children = array();
        if (Zend_Registry::isRegistered('Zend_Acl')) {
            $acl = Zend_Registry::get('Zend_Acl');
            $roles = $acl->getRoles();

            foreach ($roles as $potentialChild) {
                if ($acl->inheritsRole($potentialChild, $role)) {
                    $children[] = $potentialChild;
                }
            }
        }
        return $children;
    }