1) leased line with no real IPv4 home;
2) IP phone can not Ipv6;
3) Office IP-PBX on Asterisk with a bunch of useful peers, but no external IP;
4) Bonus — you have another router on dd-wrt with external IP.
5) Admin rights on the PBX, phone, router.
The task — to connect the house phone to a PABX.
Trivial solution — put the stub of Asterix for the router, write in ATS another feast, the phone connects to the router. Alas — when running there's a torrent of the normal quality of the voice can be forgotten.
Is there any non-trivial version of the "make friends" phone and a PBX without external crutches? Providers at home and at work are different to external IPS unrealistic, to pay money to a third-party VoIP providers, the toad presses.
Office Asterisk Hardway, Armagh, version 1.2, to load additional modules such as Skype connect to it will not work.
The situation is completely hopeless or is there a chance?