You can configure CUCM to send your company name but your provider will need to add this to your services and there may be a cost for it. Keep in mind that the person you are calling also has to have this service enabled on their account.
@maxwellmaxjohn Yes, what you desire is possible. It is not a function of "Jabber" the end user client, however, and CNAM is generally in addition to the calling party number, not instead of. If you want to mask the calling party number so that your employee's direct numbers are not sent, you can do that part in CUCM by modifying the external number mask on the line configuration.
CNAM is is a function of the following:
1. Your PSTN provider and if they support and you are contracted to allow CNAM sending. This is often an additional cost.
2. Configuration on your side of the phone system, trunk/trunk group, and/or voice gateway. This part is dependent upon what trunk type/protocols are in use, but for SIP while this is how to restrict calling party name, you can see many of the interaction points in this eloquent post: https://community.cisco.com/t5/ip-telephony-and-phones/restricting-calling-name-on-sip-trunk-in-cucm/td-p/2663887
