I am working on a prototype whereby i shall be using a voicemodem and a driver i will be programming to act as a gateway (i.e. replace the voicetronics/linejack cards and the PSTNgw program).
Then i’ll use openphone as an H.323 client.
So, as you can imagine, openphone client doesn’t require special hardware… only PSTNgw requires special hardware (i.e. voicetronics or linejack).
Hope it helps you.
If someone is doing, or has done a similar project, please email me on firstname.lastname@example.org