UBB.threads PHP Forum Software Community Forums UBB.classic UBB.classic 6 Support Allow member to view topics, but not post?

Is this possible? I'm using UBB 6.7.1.

We have a user and we just want his ability to post to be taken away, but allow him to still login to the forums.

More information: Our forums are only allowed to be viewed by registered users, and we have restricted registration to a specific domain.