On Wed, Sep 30, 2015 at 03:50:50PM +0200, Daniel Caillibaud wrote: > VD> You're also using milters, any hints as to what the milter is > VD> configured to do? > > It's for opendkim : > > smtpd_milters = inet:localhost:12345 > non_smtpd_milters = inet:localhost:12345 > milter_connect_macros = j > milter_protocol = 3
So presumably this milter prepends another header, "Authentication-Results:" (inbound) or "DKIM-Signature:" (outbound). This "prepend" action might run into trouble if the top-most header is short and non "padded. > VD> A quick work-around would be to change the header to: > VD> > VD> X-Bulk: detected > VD> > VD> which is long enough to not require "padding". > > Thanks a lot, my users have MUA filters based on existing, so I change to > /…/ PREPEND X-Bulk: YES detected > > And it seems to solve the pb Not so much solve, as "work-around". Any chance you could build from source and try the patch? If you build the exact same Postfix release you're running, it suffices to replace just the "cleanup" program in /usr/libexec/postfix/, while leaving the rest of the install as-is. (You can save the original "cleanup" and put it back when testing is done). Do: # cd /usr/libexec/postfix # cp /build/directory/.../libexec/cleanup cleanup.new # chmod 755 cleanup # ln -f cleanup cleanup.orig # mv cleanup.new cleanup Undo: # mv cleanup.orig cleanup -- Viktor.