При оправке писем скиптом РНР Return-Path пишет не адрес....

[armix]

При оправке писем скиптом РНР Return-Path пишет не адрес отправителя, почему?
Что вообще указывает Return-Path в заголовках писем?

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[Laa]

При оправке писем скиптом РНР Return-Path пишет не адрес отправителя, почему?
Что вообще указывает Return-Path в заголовках писем?

http://tools.ietf.org/html/rfc5321 :

When the delivery SMTP server makes the "final delivery" of a
message, it inserts a return-path line at the beginning of the mail
data. This use of return-path is required; mail systems MUST support
it. The return-path line preserves the information in the <reverse-
path> from the MAIL command. Here, final delivery means the message
has left the SMTP environment. Normally, this would mean it had been
delivered to the destination user or an associated mail drop, but in
some cases it may be further processed and transmitted by another
mail system.

It is possible for the mailbox in the return path to be different
from the actual sender's mailbox, for example, if error responses are
to be delivered to a special error handling mailbox rather than to
the message sender. When mailing lists are involved, this
arrangement is common and useful as a means of directing errors to
the list maintainer rather than the message originator.