Just out of curiosity, why aren't gmail accounts allowed?
FFO has always been that way (at least for the past 6/7 years that I've known about them). They normally ban all free E-mail clients and AOL addresses. I can see their point in a sense being a former FF site webmaster myself mainly because of how easy it is to make multiple E-mail addresses through AOL and any free E-mail client. This way, they can somewhat control any members who they've banned to prevent them from coming back through a different address and causing even more trouble on their boards. Although sometimes, I do think they're reaching a little bit as far as restricting access to their message board.
That being said, I know that they 'used' to allow you to E-mail them before registering and being able to get special permission to register your account via AOL or (maybe) a free E-mail client. Although I think that they might need to manually set it up for you in that case so that they could override the E-mail ban. Mind you, that this is what they 'used' to do. Chances are that Dh and the other admins got sick of this and stopped the exceptions altogether if I know their staff as well as I used to.
A little off topic but ZeaLitY, I don't know who your webhost provider is, but shouldn't you have access to making a POP3 (or at least forwarding) @chronocompendium.com E-mail account? If you do, you should have no problem registering on their board with that.