Y.S. wrote:
The MAIL FROM parameter does not tell us where the mail is from,
only the bounce address for that email. The assumption is that
whoever is the bounce address is, is probably the sender,
but in many cases especially mailing lists, that is not true.
As a matter of fact in some protocols such as SMTP AUTH,
the sender's identity is passed in an SMTP extension separate
from the bounce address.
Or the other way up:
The assumption is that the address given as the sender in the MAIL FROM is
useful as the bounce address.
The MAIL FROM argument is *used* for bounces, but it's use in LMAP
doesn't seem to be contrary to its purpose of specifying the
"sender" mailbox:
rfc821 3.1.
The transaction is started with a MAIL command which gives the sender
identification
rfc2821 section 3.3
The transaction starts MAIL command which gives the sender identification.
4.1.1.2
The reverse-path consists of the sender mailbox.
We've got only one kind of data which can be used for any number of
puposes. LMAPs are authenticators using this data.
This can't fairly be called overloading, since the argument is always of
the same type.
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