[exim] blocking part of a relay

I need to figure out how to block the origionator of a message.

I have mail relayed to me. Here is part of the header;

Received: from mxout3.mailhop.org ([63.208.196.167] ident=mailnull)
        by my.homeip.net with esmtp (Exim 4.60)
        (envelope-from <widgeteye@???>)
        id 1F0Z30-00084d-Jx
        for larry@???; Sun, 22 Jan 2006 00:49:58 -0600
Received: from mxin2.mailhop.org ([63.208.196.176])
        by mxout3.mailhop.org with esmtp (Exim 4.51)
        id 1F0Z30-0002Wz-3R
        for larry@???; Sun, 22 Jan 2006 01:49:58 -0500
Received: from web42207.mail.yahoo.com ([66.218.93.208])

mailhop.org is the relaying agent. As you can see widgeteye@???
is sending me an email. How do I block yahoo.com from sending me mail
through my relaying address without blocking the relay address?

I have tried puting yahoo.com in the acl deny hosts but it doesn't work.
If I block the relaying agent, mailhop.org, then the logs tell me that
yahoo.com was blocked. :)


I have read and read the spec.txt but I haven't figured this one out yet.

Any help would be appreciated.

BTW, I don't really want to block yahoo I'm just using it as a test.

thanks






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LINUX is simple. It just takes a genius to understand its simplicity.