> -----Original Message----- > From: owner-postfix-us...@postfix.org > [mailto:owner-postfix-us...@postfix.org] On Behalf Of Wietse Venema > Sent: Wednesday, January 11, 2012 2:04 PM > To: Postfix users > Subject: Re: Including state information in Received fields > > Postfix writes the Received: header at message arrival time. The > decision to add a Received: state field must be made before the > "250 OK" in response to end-of-data, after the message is frozen (*). > Once Postfix sends "250 OK" in response to end-of-data, there is no way > that a Received: header can be replaced without violating the RFC > requirement that mail not be lost due to frivolous causes.
A quarantine instruction from milter is returned by the EOM callback before the DATA 250 is sent (has to, or SMFIS_REJECT couldn't be implemented, for example). I think that's the one case that seemed most obvious to me, and it also seems to fall within these design parameters. I don't think you have to worry about the other states the draft talks about, as they're mostly to do with things that are implemented outside of an MTA (MLM hold-for-moderation, for example). But design issues aside, would you consider implementing it at some point? Indications of interest like that would be useful input to the IETF. -MSK
