I wasn't able to confirm it since I've not moved to 2.3 yet and the 2.2 code is different, but this should happen if there are characters from 0x01 to 0x1f or from 0x7f to 0xff in the local part.
Yeah, I was running 2.2.x prior to my upgrade and never encountered this.
By the way I noticed that if Postfix has SMTPUTF8 enabled, then it won't hand off messages with this content to Dovecot since Dovecot does not advertise support for SMTPUTF8. If SMTPUTF8 is unavailable or disabled then Postfix passes on those characters. I suspect that Ralph has SMTPUTF8 turned off.
Ah I see:
When a message is received with the SMTPUTF8 request, Postfix will deliver the message to a non-SMTPUTF8 SMTP or LMTP server ONLY if:
- No message header value contains UTF-8.
- The envelope sender address contains no UTF-8,
- No envelope recipient address for that specific SMTP/LMTP delivery transaction contains UTF-8.
I wonder if this will break a lot.
-- Ralf Hildebrandt Geschäftsbereich IT | Abteilung Netzwerk Charité - Universitätsmedizin Berlin Campus Benjamin Franklin Hindenburgdamm 30 | D-12203 Berlin Tel. +49 30 450 570 155 | Fax: +49 30 450 570 962 ralf.hildebrandt@charite.de | https://www.charite.de