I have an OLD PAP2T (from when VFX was first launched I think - 7 or 8 years ago). It's setup as follows:
Vigor 120 -> Airport Express (bridge mode)
-> Airport Extreme (wifi extended) -> PAP2T via ethernet.
In the past, I've used the pap2t from London, so I suspect SNAP isn't the issue.
The phone works fine, mostly. I can pick up the phone, and make a call. I can then call it, and it rings. No issues there.
However, if I leave it for a while (not sure - we don't get many calls :) next day for sure, may be shorter) and someone calls, the phone doesn't ring. I get the emails saying someone called, and voice mail, but no riningin. Pick the phone up, and it's all good again.
I assume a NAT somewhere is dropping the connection and not telling the PAP2T to reconnect. It could be DHCP, tho it dial immediately, so I doubt thats it.
Any ideas how to fix it? The airport express doesn't have a NAT timeout setting, and the pap2t has a NAT Keepalive, but I can't edit line 1.
saying "call WXC" is a valid response :)