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In failing to resolve the ammo counter bug in ACS, I decided to remodel it in a much simplified form. This is the result.
What does it do, exactly? The principles are the same as the ACS; fire the ECM and throw stuff overboard to deter missiles. That's where the simularity ends.
Missile Spoof uses flares, which it makes with a fraction (.1 LY) of ship's fuel. As long as you have fuel, then you have white-hot flares to scatter. It uses the ECM if your tanks are dry, and both if you have fuel, so keep an eye on your fuel guage.
Remember: No fuel = no flares = a far higher chance of getting clobbered by a Hardheaded missile or torpedo.
Naturally, this resolves ammo counters going wrong by eliminating the ammo counters. Also eliminates the need to buy specialized ammo magazines.

For the curious, being simpler also means being a little dumber: While it no longer requires the missile anylizer, it chucks out flares - and nibbles a bit of fuel - each time a missile is fired your way, and no longer checks for missile type.
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Installation:
1) Sell your ACS (if you have it) then save
2) Remove the ACS oxp (if you have it) from your AddOns folder
3) Place Missle Spoof.oxp in your AddOns folder
4) Head for the nearest TL 8 or better station and spend 1000cr for a Missile Spoof
5) Have fun!
UPDATED: Now checks for standard missiles (the most common type used against the player) and doesn't drop flares if standards are detected; uses less fuel that way. Sell option added, full refund.
http://www.box.net/shared/k6cq6809jnodnbueklsu