I thought one thing that may encourage users to post in the counselling forum is to allow registered logged on users to post a topic annonymously without having to log out and put a topic or message up as a guest.
Anyways, I don't think its thaaat much of a hardship to sign out and log in under a the anonymous user name. Sure, it takes a bit more pointing, clicking, and typing, but I'm sure you do a lot of that anyway.