Is it possible to control air conditioning with the X10 and ActiveHome PRO system?
I've heard air conditioning remotes are different to TV remotes in the way they send signals.
If you get BVC and the USB-UIRT (see:
http://www.wgjohns.com/bvc.htm) you can teach BVC (with a little trial and error) the codes from your air conditioner remote and then either control it by voice, or by creating a "Listener" in BVC that will respond to a specific AHP X10 address (which would allow you to use a AHP macro to send a signal to BVC and get BVC to send the IR signal to the air conditioner).
I have a "Everstar" air conditioner that I can control this way.
One drawback to this approach is that you have to have the computer that is running BVC running all the time.