delivery-queue - SMTPUTF8

[crpb]

gromox/mda/smtp/cmd.cpp

Lines 83 to 85 in 5d1e4af

	"250-HELP\r\n"
	"250-SIZE %zu\r\n"
	"250 8BITMIME\r\n",

root@grom-deb:~# telnet localhost 24
Trying ::1...
Connected to localhost.
Escape character is '^]'.
220 grom-deb.testsystem.de Service ready
EHLO grom-deb.testsystem.de
250-grom-deb.testsystem.de
250-PIPELINING
250-HELP
250-SIZE 67108864
250 8BITMIME
451 Timeout
Connection closed by foreign host.

is that by chance a static thing and we are just missing SMTPUTF8 here to get around problems like

https://community.grommunio.com/d/2375-smtputf8-not-supported-on-internal-ports-24-gromox-and-2693-sphinxarchive

And

Von: Mail Delivery System <MAILER-DAEMON@THISSERVER.de>
Gesendet: Montag, 3. November 2025 08:23
An: SOMEONE@THISSERVER.de
Betreff: Undelivered Mail Returned to Sender


This is the mail system at host gro.....de.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.


If you do so, please include this problem report. You can
delete your own text from the attached returned message.

                   The mail system

<someoneelse@THISSERVER.de>: SMTPUTF8 is required, but was not offered by

    host ::1[::1] 

[aunovis-herzfeld]

Thanks for opening this issue — I can confirm the same behavior on my side.

When a message requiring SMTPUTF8 is relayed from an external gateway to a Grommunio system, Postfix bounces it with:

SMTPUTF8 is required, but was not offered by host ::1[::1]

The local Gromox SMTP listener (port 24) and archive listener (port 2693) both announce only:

250-PIPELINING
250-HELP
250-SIZE 67108864
250 8BITMIME

→ No 250-SMTPUTF8 line.

As a result, messages that contain UTF-8 characters in addresses or headers are rejected internally, even though external hops (e.g. relays or gateways) fully support SMTPUTF8.

Example excerpt:

postfix/smtp[…]: status=bounced (SMTPUTF8 is required, but was not offered by host ::1[::1])

It appears that the internal Gromox SMTP service simply does not yet advertise SMTPUTF8 capability, which leads to local delivery failures for UTF-8 mail.