Since this thread is getting a bunch of extra attention, maybe I should say a bit about what JForum is. It's an open source Java web app for hosting public (or private) discussion forums. It works with the common SQL databases, and has a number of advanced features such as fine-grained permission and access control, thread bookmarks and thread and forum watching, powerful search, and numerous configurations for fine-tuning its behavior. In my opinion (biased, as I'm one of the committers to JForum) it's the best Java-based discussion software.
I was born with webbed fish toes. This tiny ad is my only friend: