Mohan, as a quick fix for this requirement you could suggest a commercial solution. Blackboard, for example, licenses software from another company to add this to their software. You can create an account on blackboard.com to test it in context:
http://coursesites.blackboard.com/It is a nice tool, a "virtual classroom" with a chat (where individual users can be blocked or given the floor), whiteboard (which can also load external websites for group scribbling), and realtime Q&A. Here is a demo from the company that makes it: http://www.tutornet.com/Demo4Web/index.html It might even have a decent API so data can be archived in the DB.
I would be interested in hearing about open or closed alternatives that are strong enough to warrant the time, energy, and/or money. Anyone?
I set up a test course on one of our local installations of WebCT for Mohan, if anyone is interested in testing WebCT (3.6.x Standard Edition) send me a mail.
