Block for VIA headers
I’ve deviced a block that will block many proxy servers. Not all, but many. Problem is, it also blocks regular people who use a proxy as part of their ISP setup.
This block could be useful for dropping in during a prolonged comment spam run, like the one I had yesterday.
But Spam Karma would probably do a better job. Or even the built in blacklist in WP!
So, given the disclaimers, and warnings, here it is: