Forward source DID Indication to Extensions

i’m trying to do a special deployment on Asterisk.
I’m running a VPS with Asterisk and FreePBX as GUI. All works fine and i can get trunks and extension registered.
Since i’ve got some trunks, i need to manage them via DIDs and via Inboud Routes: all works fine.
I run this to have a real mobility (my house dsl isn’t good so if i need to connect in mobility i don’t have to register to my home’s asterisk server but i will register to the VPS, that’s better).

After some days i find useful to install in my house an old Cisco SPA9000 (that i had in garage for some years) with six old SPA942 phones.
I use this SPA9000 with the PSTN (via SPA3102) registered as LINE2 and the FreePBX “trunk” via SPA9000’s LINE1.
All works fine, inbound and outbound, but the SPA9000 can’t manage the Ring Groups. This because it doesn’t receive the “source” DID indication from Asterisk.

Is there any way or any workaround to forward the incomind DID to the extension? I don’t want to apply this rule to all the Asterisk’s exntensions (extensions that i use on mobiles doesn’t need it).

This will be useful too if i setup a trunk to a patton that my girlfriend have in her shop (old PBX that managed two inbound DIDs from the ISDN provider)

I’m running FreePBX as GUI and Asterisk’s version is 11.9.0
All runs on Centos 6.5


${EXTEN} on initial entry to the dialplan contains the DID number (assuming you have real DID, rather than a single number taken from an ITSP’s DID. Getting the initial ${EXTEN} under FreePBX is a question for the FreePBX people.

How you get that displayed depends on the outgoing channel technology and the capabilities of the phone. Some people use ${CALLERID(name)}.