If someone faced with a similar problem, I solved it differently.
Namely, I started the asterisk server, it caught the Linksys 3000 (PSNT to SIP) and Huawei E1550 (SIP to GSM, GSM to anywhere).
The solution is difficult, but very interesting. You just have to read "Asterisk. The future of telephony," to climb a bunch of forums, and spend about a month of free time setting with the study :) But I wonder and expand!