Using Live ID in Web Application

I have a web application in asp.net(vb.net). We have approx 200 users of this application. we want to use a feature where between the defined groups, users can interact with each other just like an IM session. But that should be in my application area and I should be able to record the conversation for future reference.

Also What it is going to cost me?

Any Help will be appreciated on this.

[419 byte] By [PawanBansal] at [2008-2-20]