Bruce -
People's passwords aren't the problem. The trouble is that the spammers have software tools that automatically go through the registration process and post these messages.
I was granted moderator status so that someone could delete out the spam as it pops up. However, I have NO access beyond that; nor do I own or control the site. I'd be happy to do more, but the person/people in charge have their own plans - which I understand and respect.
Take care,
--Noel