On Sun, Jan 12, 2003 at 09:58:50AM -0800, Todd Lyons wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
> 
> Junjiro Okajima wanted us to know:
> 
> >and recently, particulary in this mailing list, they use valinux.co.jp
> >in the domain-part of From: header. same as mine!
> >of course, everybody knows it is a lie by checking Received: headers
> >or something.
> 
> Most mail servers when they receive mail don't want just a
>   From: username
> Instead, they convert username to username@FQDN.  Where they get that
> FQDN from is up to the mail server.  It would seem really intelligent to
> use the value from the HELO or EHLO.  But what if they used
> "valinux.co.jp"?  Then your mail server appended that in, doing some of
> the dirty work for the spammers of making it hard to track down who
> really sent it.

which leads to another nice qmail-ldap feature, sanitycheck for mail from:
from foreign host. the "must have an @, domain part must have a dot in it"
(SANITYCHECK in tcp.smtp) saves me 2 GB worth of spam per month.

-- 
http://2suck.net/hhwl.html
Unix is very simple, but it takes a genius to understand the simplicity.
(Dennis Ritchie)

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