Hi friend, check this CME and Cisco IOS Software Version Compatibility Matrix link:

http://www.cisco.com/en/US/docs/voice_ip_comm/cucme/requirements/guide/33matrix.htm

Make a backup of your configuration, after you install your CME file in your flash, you need to upgrade the firmware versions on a Cisco Unified IP phone running SCCP,

enable

configure terminal

tftp-server device:firmware-file

telephony-service

load phone-type firmware-file

create cnf-files

end

You will need to reload your router if there is a new IOS and your atual configuracion will be loaded.

http://www.cisco.com/en/US/docs/voice_ip_comm/cucme/admin/configuration/guide/cmeinstl.html#wp1071374

Best regards

David