Hi Zane,
Sorry to hear that.
We do have a email-activate procedure in place for new registrations. We even have a customized (e.g. I made my own) Captcha (the visual confirmation picture) on registration page. But these just cannot stop them.
I just added a new tool to fight this, a module called Spam Words. It will detect whatever spam words we listed (in Admin panel). If found, the message will be rejected. Though the spam list does NOT apply to our active members.
Still need to test the new function.
Ken