If an email is submitted via SMTPUTF8 it will bounce
If a email is accepted via SMTPUTF8 and amavis via port 10026 is used the email is bounced. I think this happens if the mail is being forwarded.
amavis should announce SMTPUTF8 on port 10026 correctly, port 10024 is not affected
Server OS: (debian)
Server OS version: (stretch) ISPConfig version: (3.1.13p1)
remove this line from install/tpl/amavisd_user_config.master
smtpd_discard_ehlo_keywords => ['8BITMIME'],
Introduced with Postfix version 3.0, this fully supports UTF-8 email addresses and UTF-8 message header values.
A SMTP response to an EHLO command will now announce SMTPUTF8 capability by default.
relay=127.0.0.1[127.0.0.1]:10026, delay=0.2, delays=0.15/0/0.05/0, dsn=5.6.7, status=bounced (SMTPUTF8 is required, but was not offered by host 127.0.0.1[127.0.0.1])