I kicked Spamcop when they started blacklisting 127.0.0.1 so that no system logs could be sent out by E-Mail...
Why would you subject internally generated mail to blacklist processing at all? I find it a bit questionable to use any blacklists in a binary fashion (unless you're _really_ 100% in line with their listing policy, which I'm normally not unless I compose the list myself;-)). Assign a hit a weight, and only drop if you're above a treshold (and if your recipient mailbox agrees to such drops, or the threshold). And certainly only do this with traffic from the "Most Evil Internet", not from trusted networks... Just my $0.02;-)
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