Edited by author 12-09-2002 09:58 AM
Yeah, Graham talks about this limitation a little bit in his paper. Even so, I have to say I've had really good results with SpamSieve on minimalist spams.

SpamSieve is supposed to decode Base64 encoded content, which should include an attachment like that. Also, since SpamSieve parses everything, including the full headers, it does have a bit more to work with than you might think. So perhaps this is a filter-training issue. Is your spam corpus very large? When a message like that slips through do you do an "Add Spam"?