Apache for Windows and dosevasive

Hey guys and gals.

Iv recenlty come under attack a few times a week via a simple DoS attack.  When it occurs, its the same ip (a proxy) over and over.

As a temp solutions iv just been adding the ip to the "deny from" directive.  It seems to stop the attack, untill the atacker finds a new proxy to use.

I sure its one of my competitors (id like to know who  ;-0 )

I have heard of 'dosevasive' for linux.  Is there a version for windows ?

Or

Is there a firwall suite i can buy (specific name plz) that will automatically work with Apache (monitor port 80) and ban all that hammer requests ?

Thanks, Andrew