Jon Kyme wrote:
Of course a lot of this hangs on the fuzzy definition of a sender.
If I inject a message to the MTS, I'm the sender... but if the messages
passes through a forwarder / exploder, am I the sender of the message
received at the far end? The message can have the same body,
but will have a new envelope. For me, the entity that constructed the
envelope is the sender. This is why I don't have a problem with some
requrement for a forwarder to supply a new sender address. I think this is
a clarification. Others differ.
I agree with the fact that the definitions are fuzzy. There are at least
four different mail headers: "From", "Sender", "Reply-To" and
"Return-Path" for this type of information. According to RFC 2822:
"From" is "the author(s) of the message ... responsible for the writing
of the message"
"Sender" is "specifies the mailbox of the agent responsible for the
actual transmission of the message"
"Reply-To" "indicates the mailbox(es) to which the author of the message
suggests that replies be sent"
And "return path" is the error bounce address as stated in RFC 2821,
section 4.4:
"The primary purpose of the Return-path is to designate the address to
which messages indicating non-delivery or other mail system failures are
to be sent."
My reading of the entire section 4.4 implies that the MAIL FROM
parameter which the "Return-path" headers preserves as stated, is
specifically for the purpose of the bounces.
Yakov