I had deleted the message yesterday--thoroughly--and didn't think to ask
this until today.
Concerning ImageInfo, which sounds like a likely candidate, it's not
installed on my system. I have Kolab installed; it uses an earlier
version of Spamassassin, I'm not sure exactly which one, somewhere
around 3.2.x.
I'm not sure whether I can add the plugin; I'm asking about that on the
Kolab list.

John Hardin wrote:
> On Thu, 14 Feb 2008, Paul Douglas Franklin wrote:
>> I have Thunderbird set up not to show images by default. But some
>> spammers have discovered a way to encode their images so that they
>> show despite my settings. The latest example was exceptionally rude.
>> Is there some rule that I could add to my local.cf to catch any
>> e-mail that tries this end-run?

> Would it be possible for you to post the entire raw message somewhere
> so we can see how they are doing it?

Paul Douglas Franklin
Computer Manager, Union Gospel Mission of Yakima, Washington
Husband of Danette
Father of Laurene, Miriam, Tycko, Timothy, Sarabeth, Marie, Dawnita, Anna Leah, Alexander, and Caleb