Core Issue
The user is unable to add the ccm-manager command on a 1760 router running c1700-sv8y-mz.122-15.T5. Therefore, it is impossible to configure for Media Gateway Control Protocol (MGCP).
Resolution
To support MGCP for Cisco CallManager on a 1760 router, Cisco IOS Software version 12.3 (2)T, 12.2 (15)ZL or 12.2 (13)ZF/ZH is required.
Make sure your Cisco CallManager version supports it by trying to add a new gateway. Determine if it allows you to select a 1760 router.
For more information, refer to these documents: