Guido van Rossum
And not necessary. Base64 spam invariably has telltales that Bayesian amalysis will pick up in the headers and MIME cruft. A rather large percentage of it is either big5 or images.
I'd be curious to know if that will continue to be true in the future. At least one of my non-tech friends sends email that's exclusively HTML (even though the content is very lightly marked-up plain text), from a hotmail account. Spam could easily have the same origin, but the HTML contents would be very different.
Well, consider. If your friend were to send you base64 mail, it probaby would *not* come from one of the spamhaus addresses in bogofilter's wordlists. The presence of base64 content is neutral. That means that about the only way not decoding it could lead to a false positive is if the headers contained spam-correlated tokens which decoding the body would have countered with words having a higher non-spam loading. -- <a href="http://www.tuxedo.org/~esr/">Eric S. Raymond</a>