Hello
We have migrated our email services from a server, which did not support IMAP and folders, therefore threated the plus sign + as a normal character in a part of an email address.
Our new server delivers the emails via lmtp to dovecot.
the few users which got a + character in the username first could not log-in (fixed by adding + to auth_username_chars). Now the next problem turn out to be, that the lmtp listener stripps everything after the + sign.
The MTA correctly sends the whole email address, so it's not the MTA's fault. It can easily be tested by connecting to the dovecot LMTP listener IP address by telnet:
220 grautvornix.imp.ch Dovecot ready. mail from:<nobody> 250 2.1.0 OK rcpt to:<b+enoit@iscan.ch> 550 5.1.1 <b+enoit@iscan.ch> User doesn't exist: b@iscan.ch
I could not find any configuration parameters for the lmtp listener or userdb service to tell it what to do with the + sign. Did I miss something, or is it impossible to have the + sign accepted as a normal character in an email address?
Kind regards -Benoit-