Can you provide more info?
How are you trying to use this? Are you going to use this router as a CallManager express or in conjunction with CallManager server?
Can you provide a sh ver and sh run and a sh diag from your router? Do you have a design document of the set up that you have in mind?
Also please note that if you want to change the feature set of IOS that comes with the router, you need to purchase the software from Cisco, as you need to be able to upgrade to another IOS. This upgrade is not free.
Looking forward to hear more about your set up to be able to help you.
Regards,
Farbod