[Mimedefang] Re: Great open letter about anti-virus, emails, bounces, etc.

[Royce Williams]

Tony Langdon wrote:
> The poroblem with this is you get sites like mine which send mail
> (legitimately) from a couple of domains.  Using the ISP's mail server isn't
> always an option, because they may refuse to send mail from the alternate
> domain, and even if they did accept it, then that may still cause problems
> if you attempt to look up the PTR or MX records for the source domain and
> see that there's still a mismatch.

Hrm ... I would expect that most ISPs would base your "relay-ability"
on whether or not you were coming from their IP space.  If you're coming
from a single site (if I understand you correctly) then you're coming
from IP space that they own, which should give you a blank check for
relaying through the ISP's mail servers -- regardless of what domain
you're claiming in your 'RCPT TO:'.  If Joe User claims to be somebody
like billg at microsoft.com (a domain I happen to not host for anyone :) ),
as long has he's coming from my IP space, I don't care.  Anything else
proved to be too much of a headache for us -- too many folks need to do
what you're describing.

Of course, just because we do it doesn't mean that the rest of the world
does.

Royce

-- 
------------------------------------------------------------------------
Royce D. Williams
ISP System Administrator III - ACS IP/ISP
907-565-2267    PGP key: 0x3FC087DB     http://web.acsalaska.net/~royce/