So as admin and upgrading to v4, I went through the Community Server 2007 SP2 forums list and clicked on each Chat link to set up a lobby for each. Open, connect, then close. After the first two, the third one would just freeze up and never respond. I had to close all Internet Explorer instances to get it to reconnect to the web server at all, even just Communiy Server. I continued down the list but had to keep doing this for every two or three forums / chat lobbies.

 

I'm suspecting that either global.asax or the forum integration code is having conflicts or lockups or something with the browser's session or session cookie.

 

The CPU usage on either client or server does not noticeably go up in Task Manager during this time.