Is driving me crazy: Sign up bots!

[funnyspo]

This is a copy of the same post I put on vbulletin.com, until now they can't give me an answer.

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Ok, so I dont know what's up! the bots keep signing up and filling my forums with spam.

Here are the mods I have installed with no luck in stopping them:

- NoSpam!
- Enhanced Captcha Image Verification
- + the Human Verification from the forum itself.

p.s: I have also ban bunch of their ip, ip extensions, etc. I can't stop them! please help! Is been over a month dealing with them.

Please tell me you have a suggestion?
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Please help!

Some of their answer are:

Again, its completely possible for a human to be registering accounts, and handing the account over to a bot.

Which I dont believe since my site is not big at all!

[Swampfox]

Use the question/answer option, captcha is useless

[funnyspo]

let me try that! if not I will be banning all those f*ckers!