[Buggy222]

I tried several SIP vendors and only found one that worked for me on my 6800. Part of the problem is different voip's seem to use different terminology or settings that I didn't understand. I used Schap's SetupVOIP version 0.3 (found on the forum).

The provider that worked for me was InterVoip.
User Account = The name you pick without any @abce on it.
Password -= what you pick
Registrar address = sip.intervoip.com
Port = 5060 UDP (make sure this port is forwarded on your router)
Proxy address = same settings as registrar address
The URI address just appeared after I said DONE and then went back and checked it. What appeared was sip:username@sip.intervoip.com

There is an options tab where you say when it should use Voip.

When I went to my PHONE, with WiFi turned on and connected, instead of Sprint is said InterVoip.

I bought credit at their website and was able to dial my son and talk to his phone. Had to use plug in earpiece and mike. The number also had to be in an international format. For my son who has a San diego number, it was 001619xxxxxx where 619 was the area code.

I tried FonoSIP, Callcentric and DrayTEL without success. Maybe I could not get their SIP setting correct, so if someone has the answer, let me know.

At least I can confirm InterVoip worked on a Mogul 6800, at least with my home WiFi. I have yet to try it on another WiFi system.

Good luck