mac computer telephone interface

We wish to investigate developing a computer to telephone interface for mac that would enable us to dial out on our cisco 7971 phones from the computer. The phones are loaded with the SIP firmware and reportedly supports CTI. Interface should work using the mac 'Services' feature set such that you can simply select text in any application, control click, choose services then 'dial'. Stage 2 would be required to translate the number. eg (888) 555 5555 should be translated to international format being based on country code configured. So in australia 001118885555555 should be dialed. Probably a popup to allow user to confirm translated number. Stage 3 would be address book integration. e.g., click number on contact then dial it. App should be developed in java. There really shouldn't be much UI apart from the settings screen which should be a mac system preference pane and possibily a popup when dialing .