Looks like you would have to recompile postfix with changes to
smtpd_check.c,
https://github.com/vdukhovni/postfix/blob/c8e31ae510e006127934ce54413a829933ccae9d/postfix/src/smtpd/smtpd_check.c#L3818
On Sat, Sep 8, 2018 at 3:18 PM Stefan Bauer <cubew...@googlemail.com> wrote:
>
> Hi,
>
> using
>
> smtpd_sender_restrictions = reject_authenticated_sender_login_mismatch
> smtpd_sender_login_maps = hash:/etc/postfix/login_maps
>
> rejects user with invalid mail from domain with
>
> <a@b.c>: Sender address rejected: not owned by user abc; from=<a@b.c>
> to=<u...@remote.tld> proto=ESMTP helo=<[192.168.0.173]>
>
> How can i customize this reject message?
>
> Thank you.
>
> Stefan
