ProxyPass is the only one that works.
You cant stop pass hackers by blocking them anymore, you have to stop the proxies they use to attack you. ProxyPass is the only program on the net that blocks proxies attacks. Anything else is just pissing in the wind.
Lets say a pass hacker attacks you through 40,000 proxies. You block each one but he gets ( depending on settings ) 5 guesses on each proxy. If the hacker still gets 200,000 tries at a good user/pass then what are you really accomplishing ? He still gets to run a pass list against your server, your server gets loaded down, your logs fill up with 403 errors. Its pointless..
With ProxyPass any request from an open proxy gets no response. The hackers dont even get a single guess. My bandwidth is down by 20% and my server load dropped down by 40% when I switched from Iprotect to ProxyPass.
Do the reading on ProxyPass.. I dont usually endorse anything but the program just works.