David Gerard wrote:
With Bayesian filtering on the message body, the sort of mail from humans that I've seen get eaten by Thunderbird is messages from IT recruiters, who seem to write spam natively.
There were actually a few scams which claim to offer employment. When you give them your details, they use them for identity theft -- applying for credit in your name, for instance. So it's quite possible that the IT recruitment messages you saw were in fact spam.
GMail eats stuff from Wine-Users, presumably because it talks about the same Windows software that shows up advertised in spam.
Thunderbird once identified a long, wordy plaintext email from a university colleague as spam. Presumably it had been trained to recognise rare words as being spammy, following the keyword stuffing trend in HTML and image spam. Server-side filtering is more reliable, in my experience, especially when the filtering software has human care and feeding.
-- Tim Starling