>> 2. Getting Dovecot to present and interpret AUTH=LOGIN [...]
> In your auth{} block, add/change mechanisms to:
> mechanisms = plain login
Ah, okay. I figured that it wasn't supported already because the
example in the .conf page ("plain digest-md5 cram-md5 apop
anonymous") doesn't include it. That's not an exhaustive list, then.
Thank you!