[exim] Testing a White List Trick

Testing a white listing trick. What I'm doing is saving the host IP
addresses of all messages that are clearly ham in one file and all
messages that are spam in another file. Then what I'm doing is finding
all the hosts over a weeks worth of data where I get 10 or more hams and
0 spam. I'm then using this list of IP addresses to bypass Spam Assassin
and deliver ham.

The advantages (I Hope) ....

Less false positives.
Faster Processing.

Thoughts .... ?