检测Router :: connect中的子域

I'm busy with building a website with an admin-area in the Lithium PHP Framework. However, I would like to access the admin area via a subdomain like:

https://admin.mywebsite.com/{:controller}/{:action}/...

I've made a subdirectory in the controllers directory (app/controllers/_admin) and defined a route in routes.php:

Router::connect('/admin', array('admin' => true, 'controller' => 'Base'), array( 'continue' => true, 'persist' => array('admin') ));

and the following in media.php:

Dispatcher::config(array('rules' => array( 'admin' => array( 'controller' => 'app\controllers\_admin\{:controller}Controller' ), };

Now my app knows that it should use the controllers as app/controllers/_admin/{:controller}Controller.php when the query is starting with /admin. But instead of this subdirectory, I would like to use a subdomain like admin.mywebsite.com. Does anyone know how I can realize this in Lithium? I can't find anything about it in the documentations or Google. How can I let the Router 'listen' on a subdomain?

Looking forward to your answers! :)

There are a few different approaches to this, but if you're setting up the admin with its own set of routes, you can check out Router::attach(): http://li3.me/docs/lithium/net/http/Router::attach()