They know today because the most recent Delivered-To line contains the envelope recipient as it was when the message was caught by the catchall. By reinjecting messages that are subject to a catchall you discard that information and transform the env. recipient of every message to the same value; that of the catchall target address. This will break the programs named above (or force them to parse To: headers with the resulting, well documented disasters that approach entails. For example fetchmail would resend this message back to the mailing list instead of on to the real recipient. After all, that's what the To: line says to do!).
Accurate recording of the envelope in the Return-Path and most recent Delivered-To header line are vital for catchall users of MDaemon, getmail, fetchmail, vodmr, etc. Please don't remove that.
I have never used MDaemon, getmail, fetchmail, etc, so I didn't see this problem coming.
The purpose of changing it to an email address was to force vdelivermail to parse the catchall recipient's .qmail file. However, assuming my vpopmail patch gets in the next release, vdelivermail will parse the user's .qmail file even if a Maildir/ is used.
I thought the Delivered-To header was supposed to be set to the final recipient... so I didn't think it would matter to use the address in the catchall.
That said, we can just tell people to use version x.x of vpopmail to parse .qmail files via a Maildir/ in the catchall.
Jeff
