May I know the complete call flow here? For eg IP phone -- CUCM -- SIP -- Router -- Pri -- PSTN.
Was this working before?
What do you see on the cell phones?
May need to run debugs on gateway, once we identify the call flow?
Does Caller ID work to other corporate land lines? Is there a difference if caller ID is announed to different carriers? Check with your carrier, you may have SiteA with NumberRangeA, GatewayA and SipTrunkA if you maybe allowed to send caller ID but say all SiteA but SipTrunkB perhaps your carrier blocks this.
The detailed information is key for people on here to help you.. I suggest raise a case with your SIP carrige provider and run some call scenerios, they should be able to debug their end and tell you what infomration is required to be sent.
Need a bit more of a description to provide some help.
Is this when you call cell phones or when cell phones call in?
Can you provide some more infomration about the dial plan, gateways, etc.. are the gateways redundant for instance or is it once setup per site with a DID range for each site, etc