I am facing a peculiar issue with displaying original caller?s CLID when the IP phone is forwarded to some external phone.
IP phone #7777 has DID 03-5555-7777. The Pilot number of PRI is 03-5555-7000.
The phone is forwarded to an outside phone X.
When this phone calls any outside phone, the CLID displayed is 03-5555-7777.
But when an outside phone say, 080-6666-6666 calls IP phone 03-5555-7000, the call is forwarded to phone X but the CLID displayed on phone X is 03-5555-7000 and not 080-6666-6666.
If it helps, the provider is NTT in Japan. I tried using different PRIs of NTT but it always sends pilot number. Interestingly when I tried JT lines without changing any CCM settings, the CLID was displayed correctly (080-6666-6666).
But before jumping to ?Its da provider? conclusion, I want to make sure am not missing anything :)
Normally, you are not allowed to present any number that is not been assigned to you as calling number and expect that is displayed o n the called phone. That would allow a malicious person to make calls pretending to be someone else.
You have found that the JT provider allows you to do that, that also happens in some places in the US, but it is an exception, not the rule.
Try asking NTT if they would allow you to do the same, let us know how it goes.
Hope this helps, please rate post if it does!