Dear exim & dovecot users,

posting on both mailing lists as I am not sure who has the ultimate responsability for this field.

I am trying to set up a mail server for multiple domains in my VPS. So I managed to set up the authentication through a dovecot authenticator, which relies to a sqlite database. I would like that, from the database perspective, a query has, as input parameters, both the username and the domain to check the password.

For this purpose, I am requesting that the SMTP account is in the full form username@domain.com. When forwarded to the dovecot authenticator, I can extract the user with %n and %d. This works, but it has a utter drawback: emails are sent repeating twice the domain in the Return-Path field, e.g. :

Return-Path: <"user@domain.net"@domain.net> Subject: Re: Hello To: nuquaquaraqua@gmail.com From: user user@domain.net

How do I properly fix the field Return-Path now?

dovecot --version: 2.2.25 (7be1766) Exim version 4.87 #1 built 28-Jul-2016 18:38:04

Kind regards, Quaquaraqua