Hello Timo and other dovecot-dev or users,It looks like Dovecot accepts (with APPEND command) messages that
begins
with 'From[SPACE]' line, which are not valid from RFC 2822 point of
view.
Additionnally, Dovecot will store them as they are APPENDed, I mean
with the starting 'From[SPACE]' line, which generates a bad Maildir
format.
http://www.qmail.org/man/man5/maildir.html states the following :
<< Each file in new is a newly delivered mail message. The modification time of the file is the delivery date of the message. The message is delivered without an extra UUCP- style From_ line, without any >From quoting, and without an extra blank line at the end. The message is normally in RFC 822 format, starting with a Return-Path line and a Delivered-To line, but it could contain arbitrary binary data. It might not even end with a newline.
-- DINH Viêt Hoà