On 8 Jun 2012, at 20:49, Joachim Tingvold wrote: > On 9 Jun 2012, at 2:37, Bill Cole wrote: >> That sort of feature in a MUA is fundamentally misguided. As >> described it is an exercise in intentional deception. > > Sure. Abusing completely legit features can be said about a lot of > things (-: > > That doesn't mean we have to sweep it under a carpet, using "it can be > abused" as the excuse for it.
I guess I wasn't clear... What you describe is an intrinsically abusive feature. Such a "feature" has been offered in Eudora, Pine, Mutt, Claris Emailer, and Mail.app but that fact does not change the fact that it is an essentially wrong thing to do. A MUA that injects a message into the transport system should always do so with clear identification of itself. A header-adding resend (e.g. RFC2822/5322) is significantly less problematic, and that was defined in RFC2822 because of the real-world experience with MUA's doing the simplistic re-injection of unmodified messages into the transport system with new arbitrary envelope recipients. In the modern world, there is also a practical problem because some spam filtering systems have figured out ways to do sanity checks on Received headers looking for forgeries, and will see the discrepancies of a pristine re-injection.
