Time limit before allowing registration

[ahuf]

I found a post literally months ago and can no longer locate it online. But it was for 3.8 but I think it would have worked for vb4.

I was wondering how I would go about adding a time limit to the registration page before it allows you to go through with registration.

such as you have to spend at least a humanly amount of time to complete the form.

If a bot tries to register say in 5 seconds then it would be denied registration.

Thank you for any input
-Ahuf