On 16. Feb 2026, at 21.05, max.wriedt--- via dovecot <dovecot@dovecot.org> wrote:
i just upgraded my 2.3 installation to 2.4. I like to be bleeding edge and i want to use SMTPUTF8.
I came across problems with mailboxes that have german umlauts. when enabling "mail_utf8_extensions=yes" e.g. Microsoft Outlook gives me mUTF-7 encoded folder names. Also the folder names when list via openssl s_client are encoded in mUTF-7. Am i missing something or can i disable utf8 for IMAP (UTF8=ACCEPT) only, but keep for LMTP Transport/SMTPUTF8 from postfix to dovecot?
IMAP UTF8 support is still missing various things. UTF8 mailbox names are already implemented in git main, but they are not in any release yet. There are other parts still not implemented though.