application\bootstrap.php :

Route::set('sitemap_xml', 'sitemap.xml',
	array())
	->defaults(array(
		'controller' => 'sitemap',
		'action'     => 'index'
	));

application\controller\sitemap.php :

<?php defined('SYSPATH') or die('No direct script access.');
class Controller_Sitemap extends Controller {

}

Zie ook : Sitemap XML