Dovecot LMTP rejecting mail from address with apostrophe

[Aki Tuomi]

On 17.6.2019 14.07, Michal Krzysztofowicz wrote:
>
>> On 15 Jun 2019, at 21:09, Aki Tuomi <aki.tuomi at open-xchange.com> wrote:
>>
>>
>>> On 15 June 2019 10:56 Daniel Lange via dovecot <dovecot at dovecot.org> wrote:
>>>
>>>
>>> Am 15.06.19 um 00:36 schrieb Michal Krzysztofowicz via dovecot:
>>>> Would you know if Dovecot project uses an issue tracker which is publicly available, and which I can check?
>>> I am not aware of public access to the Open Exchange AG / Dovecot OY 
>>> issue tracker. I guess that is a perk that comes with buying commercial 
>>> support.
>> This issue is in our issue tracker. Michal, can you post your doveconf -n?
>>
>> Aki
> Hi Aki,
>
> Sorry for a delay in responding. Please find my config below. 
>
> #
> #
> #
>
> # 2.3.5.1 (7ec6d0ade): /etc/dovecot/dovecot.conf
> # Pigeonhole version 0.5.5 (2483b085)
> # OS: OpenBSD 6.5 amd64
> # Hostname: smtp.example.com

<snip/>

Have you tried setting 

auth_username_chars =
abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@'

Aki