I'm not sure myself -it is authenticated properly I presume? SIP is also very sensitive to NAT - the best thing to do is make sure that UDP port 5060 is forwarded to the phone.
I'm running it against an internal Asterisk server myself, however, one of my workmates is going to try it with MyNetPhone, so I'll get him to post his findings.
MyNetPhone compatibility
I'm not sure myself -it is authenticated properly I presume? SIP is also very sensitive to NAT - the best thing to do is make sure that UDP port 5060 is forwarded to the phone.
I'm running it against an internal Asterisk server myself, however, one of my workmates is going to try it with MyNetPhone, so I'll get him to post his findings.