Windows Live Contacts API

I am trying to connect to the Windows Live Contacts REST API.

In addition to an authentication header, the URL to retrieve data
looks like this:

In ActiveResource, the site would be,
the prefix would be users/@L@XXXXXXX/rest/LiveContacts/Contacts/, and
the element would be contacts.

Is there a way for me to connect Active Resource to this REST API?
ActiveResource wants to ask for

GET /users/@L@46578b9241ad5159/rest/LiveContacts/Contacts/contacts.xml

It's the trailing XML (at a minimum) that throws this off.

Any suggestions? Can the :from option help me?