Looking for a way to deter spammers from forum boards . . .

Hey guys. M forums have been getting majorly bogged down in spam members lately.
I have already set up the process where I have to confirm everyone that comes in, so the spammers can't post (except in my "problems" forum, which has to be public).
I'm just looking for a way to block the spammers from signing up at all.
I use free phpbb, and can't really use much else because I don't know much about transferring all of the posts to another forum type. I can't afford to lose the posts I have, and I archive often.
I'd like my forums to us this setup, as vBulletin is pretty nice and nicely customizable. Granted, I need to know more php to be able to do anything more anyway.
If someone can tell me how to block spammers or transfer to a better forums program, it'd be MUCH appreciated!
Deleting spammers blows.

Jam it back in, in the dark.

Well, I can't help you much with the programming side of it, but as a temporary solution, might I suggest adding new moderators with the sole task of banning spammers, if you haven't done so already?

There's nowhere I can't reach.

Agreed with Griffin. The human element is always important in weeding out the chaff. Any automated filter or autoban system will result in more false positives or allowed negatives.

This thing is sticky, and I don't like it. I don't appreciate it.

Here I'll plug SMF; it's feature set is more comparable to vBulletin than something like phpBB ( no subforums? no attachments? can't merge topics? come on =/ ), and if you go on Converters in the download section, there's a phpBB > SMF Converter.

I forget if phpBB even has captchas (where it generates a random image and you have to type the letters you see to verify you're human), but if it does, you should enable that.

The last phpBB forum I had anything to do with was plagued by constant signups by automated bots posting ads for pharmecutical products and online texas holdem poker and the like =/

I run a forum that used to be phpBB and we eventually converted to SMF, and we've never looked back

I am a dolphin, do you want me on your body?

Thanks guys.
I have captchas enabled, and I also have an admin that helps me delete members. Mods can't delete members in phpBB. Yeah. Lame.
I do like SMF, and if there's a converter, maybe I'll just do that.
Thanks for the help guys!
Keep those suggestions rolling in though! I like a wide variety of optios when making a big decision such as this.
I'm just afraid I'd lose my current list of members, as most transfers lead to members having to re-sign. I hate that. Building from scratch when I've worked so hard to get where I'm at. You know what I mean GFF . . .
Heh.

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