Disallow users to post in "Lounge" section if they post there too much

[giraphe]

Too many of my posters just post in the "lounge" section of my site. It accounts for about 75% of all the posts.

I want to be able to control a ratio of (how many lounge posts) / (all posts). If their ratio is too high, then the script will not allow them to post / reply. I do not expect anyone to do all this for me, I am willing to learn how. But, I am somewhat unfamiliar with the vbulletin system (i.e. which files do what and their classes).

I can do the php stuff, but integrating it into vbulletin is the problem.

Would someone please tell me the best method to accomplish this?