So … because I just wasnt sure where to look and what to set, and it seems not many people use this specific configuration, as well as confusion about what I was trying to do, I had a huge mess of assumptions running amok.
I have since cleaned that mess, and the end result is almost as I like it.
First of all, the SOGo bug regarding setting ACL’s is real in my perception, the rest is not.
The real issue is SOGo setting ACL's wrong. That is, setting ACL's through the webmail, will set the rights to user instead of user@domain.com. I dare say it is wrong, because it can not process them itself either. After setting ACL's with Thunderbird and without using the 'fix' to use the AD mail property (and thus defaulting back to userPrincipalName) SOGo displays the user shared mailboxes as well.
What follows is a quick and dirty on how to get my current config and what that does. It has several undocumented features that, once you know them, really help you out here, intended or not.
- install nethserver 1 with samba ad and create users user1 and user2
- install nethserver 2, join it to that AD, install SOGo
- create aliasses for both users; t.account@domain.com and t.account2@domain.com
- log-in to the SOGo web-interface and fill in the e-mail alias as shown below:
- open ADUC and set AD property mail to the e-mail alias
Note I did not apply the userPrincipalName fix for the IMAPLoginFieldName.
Logging into SOGo now displays:
IMAP thru Thunderbird shows:

Headers while sending mail from t.account@domain.com:
IMAP:
X-Spam-Status: No, score=0.0, required= 4.0
X-MS-Exchange-Organization-PCL: 0
X-MS-Exchange-Organization-SCL: 0
X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) * on
server1.domain2.local * at Wed, 22 Nov 2017 09:39:28 +0100
X-Spam-Status: No, score=-0.0, hits=-0.0, required= 8, autolearn=no
autolearn_force=no, shortcircuit=no
X-Spam-Report: * -0.5 ALL_TRUSTED Passed through trusted hosts only via SMTP
* -0.0 BAYES_20 BODY: Bayes spam probability is 5 to 20%
* [score: 0.1791]
* 0.5 JAM_SHORT_MAIL_WITH_URL Mail with less than 150 chars and containing
* an URL
X-Process: ESTProcessDone
Received: from server2.domain.com (172.16.1.12) by
remote.domain2.nl (192.168.50.2) with Microsoft SMTP Server id
8.3.485.1; Wed, 22 Nov 2017 10:22:38 +0100
Received: from server2.domain.com (localhost [127.0.0.1]) by
server2.domain.com (Postfix) with ESMTP id C7F031802C393 for
<jeroenvisser@domain2.nl>; Wed, 22 Nov 2017 10:22:38 +0100 (CET)
Received: from [192.168.50.38] (unknown [192.168.50.38]) (Authenticated
sender: lmst01) by server2.domain.com (Postfix) with ESMTPSA for
<jeroenvisser@domain2.nl>; Wed, 22 Nov 2017 10:22:38 +0100 (CET)
To: jeroenvisser@domain2.nl
From: Test Account <t.account@domain.com>
Subject: IMAP header test
Message-ID: <c6776887-38b1-0206-f95b-8ebf250d3bdb@domain.com>
Date: Wed, 22 Nov 2017 10:22:43 +0100
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101
Thunderbird/52.4.0
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"; format=flowed
Content-Transfer-Encoding: 7bit
Content-Language: nl
X-Antivirus: Avast (VPS 171121-4, 21-11-2017), Outbound message
X-Antivirus-Status: Clean
Return-Path: t.account@domain.com
X-Antivirus: avast! (VPS 171121-4, 21-11-2017), Inbound message
X-Antivirus-Status: Clean
SOGo:
X-Spam-Status: No, score=-2.4, required= 4.0
X-MS-Exchange-Organization-PCL: 0
X-MS-Exchange-Organization-SCL: 0
X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) * on
server2.domain2.local * at Wed, 22 Nov 2017 09:39:28 +0100
X-Spam-Status: No, score=-2.4, hits=-2.4, required= 8, autolearn=no
autolearn_force=no, shortcircuit=no
X-Spam-Report: * -0.5 ALL_TRUSTED Passed through trusted hosts only via SMTP
* -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1%
* [score: 0.0002]
* 0.0 HTML_MESSAGE BODY: HTML included in message
X-Process: ESTProcessDone
Received: from server1.domain.com (172.16.1.12) by
remote.domain2.nl (192.168.50.2) with Microsoft SMTP Server id
8.3.485.1; Wed, 22 Nov 2017 10:25:51 +0100
Received: from server1.domain.com (localhost [127.0.0.1]) by
server1.domain.com (Postfix) with ESMTP id 0F063180336F7 for
<jeroenvisser@domain2.nl>; Wed, 22 Nov 2017 10:25:51 +0100 (CET)
Received: from localhost (localhost [127.0.0.1]) by server1.domain.com
(Postfix) with ESMTP for <jeroenvisser@domain2.nl>; Wed, 22 Nov 2017
10:25:50 +0100 (CET)
Content-Type: multipart/alternative;
boundary="----=_=-_OpenGroupware_org_NGMime-5635-1511342750.890552-1------"
From: Test Account <t.account@domain.com>
Reply-To: t.account@domain.com
X-Forward: 192.168.50.38
Date: Wed, 22 Nov 2017 10:25:50 +0100
To: jeroenvisser@domain2.nl
MIME-Version: 1.0
Message-ID: <1603-5a154280-b-29a18ac0@211616679>
Subject: SOGo header test
User-Agent: SOGoMail 3.2.10
Return-Path: t.account@domain.com
X-Antivirus: avast! (VPS 171121-4, 21-11-2017), Inbound message
X-Antivirus-Status: Clean
EAX: (return path wrong)
X-Spam-Status: No, score=-0.6, required= 4.0
X-MS-Exchange-Organization-PCL: 0
X-MS-Exchange-Organization-SCL: 0
X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) * on
server2.domain2.local * at Wed, 22 Nov 2017 10:39:42 +0100
X-Spam-Status: No, score=-0.6, hits=-0.6, required= 8, autolearn=ham
autolearn_force=no, shortcircuit=no
X-Spam-Report: * -0.5 ALL_TRUSTED Passed through trusted hosts only via SMTP
* 0.4 MIME_HTML_MOSTLY BODY: Multipart message mostly text/html MIME
* 0.0 HTML_MESSAGE BODY: HTML included in message
* -0.5 BAYES_05 BODY: Bayes spam probability is 1 to 5%
* [score: 0.0256]
X-Process: ESTProcessDone
Received: from server1.domain.com (172.16.1.12) by
remote.domain2.nl (192.168.50.2) with Microsoft SMTP Server id
8.3.485.1; Wed, 22 Nov 2017 10:45:12 +0100
Received: from server1.domain.com (localhost [127.0.0.1]) by
server1.domain.com (Postfix) with ESMTP id 03EB5180336F8 for
<jeroenvisser@domain2.nl>; Wed, 22 Nov 2017 10:45:12 +0100 (CET)
Received: from localhost (localhost [127.0.0.1]) by server1.domain.com
(Postfix) with ESMTP for <jeroenvisser@domain2.nl>; Wed, 22 Nov 2017
10:45:11 +0100 (CET)
From: Test Account <t.account@domain.com>
To: <jeroenvisser@domain2.nl>
Subject: EAX header test
Date: Wed, 22 Nov 2017 10:45:16 +0100
Message-ID: <001201d36376$9a34d200$ce9e7600$@domain.com>
MIME-Version: 1.0
Content-Type: multipart/alternative;
boundary="----=_NextPart_000_0013_01D3637E.FBF98820"
X-Mailer: Microsoft Outlook 16.0
Content-Language: nl
Thread-Index: AdNjdpd2gB1RuivzQiaqcxBYqUJm8Q==
Return-Path: lmst01@domain.com
X-Antivirus: avast! (VPS 171121-4, 21-11-2017), Inbound message
X-Antivirus-Status: Clean
The only 3 issues left, are mainly aesthetic, but will cause users to moan. They are:
- SOGo Webinterface displaying the username instead of the email alias in top left
- IMAP (dovecot) will display the Shared mailbox using the username instead of the Full name or the email alias.
- Returnpath for EAX mail is using the username instead of the alias. Only shows in the header.
It seems I messed op some replace actions for domain and domain2, rendering the headers a bit confusing. The part that matters is that t.account is used and not lmst01 (the user in this scenario)