code: public function agePrematurely($interval)
      {
          for ($i = 0; $i < count($this->cookies); $i++) {
              $this->cookies[$i]->agePrematurely($interval);
          }
      }
docs: Ages all cookies in the cookie jar.
  
  @param int $interval The old session is moved into the past by this number
  of seconds. Cookies now over age will be removed.