[exim] Innovative Host Blacklisting Idea

I'm trying out a new idea for blacklisting hosts. I have several email
servers for processing spam. These servers service my lowered numbered
MX records. I also have several dummy mx records that are higher
numbered than my real servers. So in theory no one should ever hit the
higher numbered servers. Especially when the IP addresses are on the
same server as the lower numbered MX.

But as most of you know spammers don't play by the rules and they try
hitting the higher MX records first thinking there's less spam filtering
there. So what I'm doing is counting hits by IP address. At the moment
they have to hit it 75 times to get blacklisted. And it's all spammers
and spam bots.

Who thinks this is interesting?