LOL! well i don't know the phone. It all end up if you know the device interface... say TV. each tv brand has a vendor code, if you know the details, you can send infra-red signal to it and control it. If you got tivo or xyz app in your PDA, it can control most of the devices, like dvd, tv, decoder, video player, etc.
so if you know the infra-red details of the device, and you can make your phone send it. it can be controlled. of coz in your case your doorgate via infra-red also ? or radio-wave?
Cheers,
Bernard Cheah