Custom Context + Call Forwarding

Hi, currently have 5 SIP trunks for 5 different users, each trunk is assigned to one user only.
I have installed the Custom Context module to allow the user to dialout through his assigned trunk only, this is working well so far.

However, now I have a few customers who want to use the Call Forwarding feature, problem is I don’t know how to make the calls forward through the right trunk, its just uses the first Outbound Route which happens to be my trunk!

Any ideas!?!?!?!?!

This might be sort of a hack, but suppose you add a little custom code to your call forwarding code that prepends the DID of the inbound trunk to the number to be forwarded to. Then you could set up an outbound route that matches the _DID|XXX. and assign it to the correct trunk. That will strip the DID (steering digits in this case) and dial the number to be forwarded to on the correct trunk.