I'm having a problem in my branch office with incoming calls from the PSTN when my 3620 router running IOS version 12.1(5)YD5 is operation in call-manager-fallback mode (SRST). There is a CallManager at a central location providing centralized call processing for remote branch offices. When there is a local call at the branch office the router receives from PSTN the digits of the called number matching a VOIP dial-peer to the central site CallManager which then routes the call to the correct IP Phone. When the wan link to the central site was down I had the problem that no incoming local calls were routed by the 3620 to any IP phone in the branch office network. I thought that using a "num-exp received-number extension-number" I would solve the problem, and I did but only when the router is functioning as call-manager fallback because when the wan link is up again the branch office is unable to receive local calls.
Is there anything that I can do to solve this problem?
Thanks in advance,