Windows Live Calendar account possible in iCal?

I am trying to sync a calendar with a friend who is a microsoft employee and therefore very loyal. He won't use a google calendar.

My goal is to have a calendar that we can collaborate on. He can edit it and add to it from Outlook, and I can edit it and add to it from iCal.

He has set up a windows live calendar and sent me an invitation to it. I am a co-owner on the calendar so I can share it.

I know that I can send a subscription link for the calendar and subscribe in iCal, but then I can only view the calendar and I'd have to log into windows live via a browser in order to make changes.

I've noticed in iCal that I can add accounts, (for a google calendar for example). I'm wondering if this is the way for me to add the windows live calendar. I just don't know what information to put in. The windows live help is practically non-existant.

Thanks