At 09:21 14-02-2008, Paul Douglas Franklin wrote:
>I have Thunderbird set up not to show images by default. But some
>spammers have

This is to block remote images.

>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 to catch any
>e-mail that tries this end-run?

The images which are displayed may be inline attachments. See the
ImageInfo plugin on how to add a rule to score messages containing images.
e.g. body ONE_OR_MORE_IMAGES eval:image_count('all',1)