[Exim] Filtering by subject

As part of my war on spam, I'm starting to filter by subject. Trouble is,
I'm doing it the simplistic way (I'm pretty new to exim), like this:

if $header_subject begins "e-Qualize your business" or
   $header_subject
begins "Avoid Speeding Tickets" or
   $header_subject begins "Proven
money-maker"
then
        fail text "SPAM is not acceptable at this site.
And you're a scumball too."
        finish
endif

I can see this getting out of hand pretty fast. I've managed to figure out
how to reject by host:


host_reject_recipients = "+warn_unknown:\

partial1-dbm;/etc/exim/host_reject_recipients"

(aside: strangely, this works on one of my mail servers, but not on another
with an identical version of exim)

I'm wondering if there's a way to do the subject filtering in the same (or
similar) manner, and if it will be better than the monolithic approach I'm
taking right now (intuition says yes, but....).


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Dennis Taylor
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The opinions expressed herein are mine. Get your own opinions!
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