[Users] Mediant 2000 and SER, caller ID issue

Hello all, Trying to debug a problem in regards to Caller IDs not being showed through our PSTN gateway. Not sure if this is an issue with the ser or with the mediant 2000 gateway or somewhere else but any help to this issue would be great. I am new to this and we are trying to solve this problem, basically one of our boxes isn't providing caller ID to the PSTN network when users are calling. Basically they will show up as "private number" when calls are initiated from inside and terminating on the PSTN networking, when they are terminating inside the ser itself the caller ID shows up with no problem, but not on the outside. We wish to have the ability to show private numbers and to show public numbers, but as far as it goes right now everyone is supposed to have public numbers. Where might the problem be? Any help would be great Thanks Nick