mail/postforward 1.1.1nb28 NetBSD

Postforward is a mail forwarding utility which aims to complement the Postfix Sender Rewriting Scheme daemon (PostSRSd).

The downside of using PostSRSd from postfix config is that all mail is naively rewritten, even when no forwarding is actually performed. Such rewritten Return-Path addresses may confuse sieve scripts and other mail filtering software.

This is where Postforward comes in. Instead of rewriting all incoming mail regardless of final destination, mail systems may be configured to pipe mail into Postforward only when forwarding needs to happen, e.g. in a users' .forward when the forwarded-to mailserver requires it, leaving non-forwarded mail unaltered by PostSRSd. Postforward will rewrite envelope addresses for piped mail using PostSRSd itself and re-inject these messages back into the queue, destined for the forwarding recipient(s).