I have a funny issue with my installation (fresh) talking to a 2N gateway with mobility extensions. Basically the 2N configures via making cell phone numbers look like SIP extensions.
When I used trixbox 2.2.4 this used to work fine, after update will no loner work.
The below is in the log file
[Apr 15 20:50:57] NOTICE[2359] chan_sip.c: – Registration for ‘[email protected]’ timed out, trying again (Attempt #900)
[Apr 15 20:50:57] WARNING[2359] chan_sip.c: Host ‘10.100.100.25’ does not implement ‘REGISTER’
Have you tried a custom extension 115 to dial as @10.100.100.25:5060?
Another way to do it is setup a trunk to the 2N, then make a custom outbound route to a list of cellphone numbers which must be higher than your local calling area outbound route.
The cellphone outbound route would then trunk to the 2N and place the call outgoing.
If you also want it to failover to your VoIP provider, you can also do this as well by adding it in.
and here is the SIP trunk I made in FreePBX:
Trunk Name : 1111
username=voiceblue
secret=XXXX
type=friend
qualify=yes
permit=192.168.0.XX/255.255.255.255
insecure=very
host=dynamic
disallow=all
canreinvite=no
call-limit=4
allow=alaw
context=from-trunk