First I want to wish everyone a Happy Thanksgiving.

I’ve noticed the same explosion of spam here that I am sure you are
all suffering from. I have not been able to find anything wrong here but
there are a couple of viruses going around building botnets these folks
are using.

To try to improve things, I’ve enabled the DCC (Distributed Spam
Checksum Clearinghouse) plugin to spamassassin. Hopefully it will help.
If you notice anything in the headers that is common to a lot of these