Problems with Shypho Italian Provider

[netmatika]

Hi All,
i have installed 3CX Phone System with Windows Server 2003 Standard...
all is ok...
i have done many test with Voipstunt voip provider but when i try to configure with shypho my system i can't make a call with this provider...
inbound call with all provider is ok and it register with server.

Can you help me? :?:

thank you

Netmatika