Don't know if the OP is still reading this thread.
Echoing what Tito1411 said, the Linux system is only the voice-mail, which is more of a bolt-on system to the phone system. The phone system itself is a different propreitary OS, and is only accessed through the programming software running on Windows.
The only thing you can do on your Mac is to hook to the serial port on the CPC, and run a few basic debugging things (as well as commands that can make the system reboot, or even destroy something critical if you are extremely unlucky).
You need the programming software to do *anything*, it has to run under windows, and you have to match the version *exactly* which is why they are asking you to try to get the version info.
The software is supposed to be only available to certified techs, but maybe somebody would have been very nice to you.
The Inter-Tel isn't made to be configured/setup by non-trained users. Sort of like your car. You can do a few things on modern cars, but to really get into it, you need specialized tools, specialized knowledge, specialized software, etc.