Moderation of new members impossible - here's why...

[CreditCardForum]

I run a financial forum and as expected, get an overwhelming number of spammers. I have put in place all kinds of countermeasures (including blocking IPs of many countries) but still nearly 80% of new members are spammers trying to get links or advertise their service.

I followed the instructions on here to set up moderation, but it doesn't work. Here's the flaw - you can set up a new usergroup of requiring moderation of X posts, but if someone signs up a new account and posts X + 10 posts, the "x" number of posts will go to moderation, but the 10 posts will go live. I just finished cleaning up over 100 posts on my forum from a member that signed up a couple hours ago and spammed the heck out of it. The first 3 posts (the number I had set for moderation before they become approved) went into the mod section for me to check, but all the others in excess of that number went live.

This is so frustrating and it's such a basic feature, you would think vBulletin would have it by default. Anyone have any ideas of how I can truly moderate posts and avoid this problem? It's becoming such a headache I can't go more than a few hours without outrageous amounts of spam.