I have a 5.0(4) CCM that we use for a lab, is it possible to upgrade it to 5.1 using the existing licenses? I think we are hitting a wall trying to lab setups with Presence and IPtoIP gateways on this version, plus our Operational system is 5.1, and I would like to avoid issues deploying once we finish testing in the lab. I have CCM 5.1 install disks and everything, but not an upgrade disk.