exim and relaying -- for ONE user

[will trillich <will@serensoft.com>]

looking for a way to accept HARDLY ANY relays -- hopefully more
than just "anybody from worldnet.att.net"...

i've got a partner who'd like to be able to send email from
serensoft.com -- but he's way out in the northeast using
worldnet.att.net, and i'm way out here in the midwest using
podunk-isp-r-us.

when he tries sending email as coming from @serensoft.com, it's
accepted if it's TO another serensoft user; but for any external
destination it gets bounced as a relay attempt, because of the
line

	relay_domains = 

in the /etc/exim/exim.conf file.

if i change it to

	relay_domains = worldnet.att.net

then he can certainly send email from @serensoft to @out-there
but then SO CAN ANYBODY ELSE using that small, tiny,
insignificant worldnet.att.net network (of thousands and
thousands).

is there some way to further restrict the relaying? i DO NOT want
any black hats turning my server into spam-o-rama. ideas welcome.

-- 
I use Debian/GNU Linux version 3.0;
Linux server 2.4.20-k6 #1 Mon Jan 13 23:49:14 EST 2003 i586 unknown
 
DEBIAN NEWBIE TIP #109 from Dave Thayer <dave@thayer-boyle.com>
:
Puzzled about HOW TO READ COMPRESSED FILES? In /usr/share/doc
there are tons of *.gz files -- they're "gzipped" to save space.
I like to use lynx to read the stuff in /usr/share/doc/*. It
handles gzip textfiles just fine and makes it easy to navigate
between files.  If there is HTML documentation you can follow
the hyperlinks.
  BTW, if you install the doc-linux-html package you get the
HOWTOs in hypertext.

Also see http://newbieDoc.sourceForge.net/ ...