I'm not a computer tech savy/software dude, but I did sleep in a Holiday in last night
Id be interested how these other forums are keeping them out. Security upgrade? Software?
I'm a mod on some other forums and have found that you need to stay on top of them to keep them out.
Once they start posting and find that the post stays up for a few days that the spam will explode afterwards.
I've been unfortunate to have to stay around the house and not get out much once I returned from Africa and have been able to get on a lot of spammers within hours of them posting to keep them off of the other forums, but it takes time to do it. I have found that those forums that the spam filters may be set a little tighter than here. I think that just to the number of then that need approval before their post even hit the forums along with their IP, email address, and a few other things being flagged by the forum software.
Another trick that the spammers are using is to create a account and the post nonsense in the forums. Replies like "great idea", "that's what I'd do", and other nonsense. Then once they get their post up they will slam the forums. We watched one spammer actually post replies for a year and his post count was well over 100 before he hit the classifieds with fake for sale items and contacting other members that were selling items.
It's a never ending job.