/** Forward to the login page. 
	* @param array $request request data to pass to the login page
	* @param string $errorMessage HTML, only to be passed if login failed.
	*/
	function forwardToLoginPage($requestData, $errorMessage=null) {
		$this->useClass('LoginPage', $this->getDir());
		$page = new LoginPage($this, $requestData);
		$page->setInformation($errorMessage);
		$page->handleRequest();
	}