upgrading to 3.6.4 spam solutions

[seo guy]

I am finally getting around to upgrading to the latest version of 3.6.4 on my forum, and I wanted to find out all I could about spam protection. We have great moderators but they are all overworked because of all the drive by porn posters, and link spammers etc.

Is there a post out there, or instructions on spam reduction for the new version, hacks etc? I don't want to make it hard for my users (Realtors for the most part) to register etc, I just want to make sure I do all I can to stop bots and spammers from clogging up our community.

Any assistance or tutorials that can be provided would be great!
Thanks guys

[Eagle Creek]

Do you already use "image processing library"-settings? (ACP => vBulletin optionms => Image Settings)

[seo guy]

Yes I have it set to GD

[Zachery]

You're going to need to enable TrueType or use ImageMagick, the standard GD option will not be effective in fighting spam. You should also enable the first 4 image captcha settings.