Wietse Venema wrote: > Bob Proulx: > > From: Some User <user@invalid> > > > > This case is mailed but the From: line is changed to be the account > > user owner of the forwarding process. The result shows up in the > > What clobbers the From: header? Postfix does not, because otherwise > you would not have received it that way, and the Postfix sendmail > command does not care what is in the From: header.
I thought it was Postfix doing this. But since you say that it is not (I believe you) then I will dig further and see what I can figure out from it. It is definitely arriving into the procmail process with the original invalid From: header because if I save it there for debugging then I see the original header. But the result from the procmail forward using the '!' operator is that it is then converted to the identity of the procmail process owner. But only for invalid email addresses in the From: header. With a valid address the line comes through verbatim. (And by valid I mean the domain part resolves.) I didn't imagine that procmail would be validating From: addresses as part of the '!' action. But I have failed to imagine a lot of things. I will dig into it further. Thanks, Bob
