I dont know if you are reffering to AP version one not working in that way, but when I got my ap v2 it says on the box 2004-2006 2.5L turbo all + 2007 wrx and sti and then on the getting started manual it lists the following cars that the v2 2.5L turbo is compatible with the following cars.
forester XT 04-06
legacy gt 05-06
outback xt 05-06
Just putting it out there so no one gets the wrong info, ap v2 recognizes which car u install it in and flashes information for that specific model. So I CAN keep my ap and use it on my sti when I sell my wrx! SWEET!! Z
12.7 @ 109