[exim] Yahoo! Groups and Spamcop?

Please forgive the not-entirely-exim related posting, but I'm having
trouble with my customers getting unsubscribed from yahoo! groups because
of SpamCop's determination to to keep blocking the yahoo groups MX
servers. This is generating serious customer noise, as you might imagine.

Aside from disabling SpamCop DNSBL entirely, has anyone come up with a
config that exempts yahoo's mail servers from the BL check? I think a
static list would be problematic, as yahoo migrates their mail server IPs
as SpamCop lists them.

Any ideas?

Thanks!
-Scott

Scott Call    Router Geek, ATGi, home of $6.95 Prime Rib
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