[Serusers] add_rcv_param() for INVITEs

Hello, is it possible to use add_rcv_param() also for Contact-HF of INVITEs, instead of fix_nated_contact()? This would make sure that the NATed End Device gets fed exactly the contact as R-URI that it announced in the INVITE: Example R-URI in Loose-Route Requests for fix_nated_contact(): Ser (1.2.3.4): INVITE device(a)4.5.6.7 Route: 1.2.3.4;lr=on Device (10.0.0.1, NAT 4.5.6.7): INVITE device(a)123.123.123.123 With add_rcv_param(): Ser: INVITE device(a)10.0.0.1;rcv_param=4.5.6.7 Route: 1.2.3.4;lr=on Device: INVITE device(a)10.0.0.1 The problem is that the End-Device, in the fix_nated_contact() callflow, has to accept a Request that is not really for this device (IP in Request-URI != IP of the Device). Imagine a Ser checkip uri == myself. This would fail without knowing the public IP of the NAT and hard-conding it into Ser.cfg. Does Ser support the rcv_param in Request-URI also? What do you think? Any experience on this? Regards, Martin