I have written a simple LMTP server in C, it will be released under the GPL V3
Description: LMTP server that delivers mail via procmail, maildrop, or deliver
This server accepts mail via the LMTP protocol and delivers it locally
by executing an external program. For efficiency it does not queue messages
on disk and returns LMTP success responses after the mail delivery program
(procmail, maildrop, deliver, etc) returns success.
This can be used as part of the process of migrating from Cyrus to a Maildir
based mail store.
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