Nevermind. I found it. I'm not sure how my mail server was working at all given the configuration error I had. Postfix had "mailbox_transport = lmtp:unix:/run/dovecot/lmtp", and dovecot was configured to run an inet_listener. Setting "mailbox_transport = lmtp:unix:private/dovecot-lmtp" and configuring dovecot to create that unix socket correctly fixed it. Wonder what I was thinking back when I originally configured that mess. heh. Everything is working now. Time to configure sieve to move spam.
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