[Dovecot] Dovecot headers at start of text returned to KMail

[Mike Abbott]

> 1272011889.M384349P30156.f12barry.office.onelan.co.uk,S=6494,W=6606:2,S

The size of this file should be 6494 bytes (S=6494) but in your attachment it is 6519 bytes.  Did something insert a header into the file after dovecot received it?  Perhaps this one, which (with a CR added) is 25 bytes, the same as the difference between 6519 and 6494:
X-Spambayes-Trained: ham

As I understand it, once messages are under dovecot's control they must not ever change at all.  Adding headers after delivery is forbidden.