we have an cucm 7.x with a 2851 voicegateway, configured with mgcp.
at the cucm service parameter I configured prefixes for the incoming calling number, so that the users can call back these numbers.
and now the problem. the user forward his phone to his mobile phone. if an call from external reaches his phone, the call will be forwarded to the mobile phone. the PSTN connection has CLIPnoScreening which means we can send out any number we want as calling number to the PSTN. So its possible in the described case,that the original calling number from external is presented at the mobile phone and not the users work phone number. But the number has now the prefixes, which I added in the service parameter. How can I discard these prefixes from the calling number at the cucm, so that the number is presented correct at the mobile phone?
The easier question is: can I modify the calling number at the CUCM at outgoing calls like discard predot or similar? I can modify the number at the gateway, cause this is MGCP.