There isn't an exact function like what your question refers to, however there is a way you can protect your forums from the general unruly users. You can setup all forums to be write only, or even read only, by a certain group besides the Users group. This way even when they register, they would belong to the Users group, but they would not have write access, or read, to your forums until you approved them.
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Scream
WWWThreads Developer
