Shane Rush <shane(_at_)red(_dot_)nymcity(_dot_)com> writes:
Also you may conclude that it is normal for all general public users to
know that they are not able to use their ISP domain address for
posting outside their ISP, unless they use the webinterface provided.
If they need to use a kiosk they will use webinterface or someone like
hotmail.
But that is not true. The restriction is on sending mail via the ISP's
SMTP server when not connected via the ISP/network. That is not the
same thing as not being allowed to use the ISP domain address in the
(RFC 2822) From:. Is this not what the Sender: header is for? That
when you send an email when "away from home" that you put your
'normal' email address in the From: header and the account and domain
name of the system which you are using the send the mail in the
'Sender:' header. So if your email address is 'me(_at_)example(_dot_)com' and
you
were sending an email from a friend's computer and her email address
is 'friend(_at_)example(_dot_)org' you would set the (RFC 2822) headers to
From: me(_at_)example(_dot_)com
Sender: friend(_at_)example(_dot_)org
To: ......
.
.
This SHOULD cause the RFC2821 Envelope-From to be set to the 'local'
account, so that the SPF record which will be checked is that for the
domain name of the system from which you are sending not your own.