Presumably your Internal License came from a data center. If so, they can have the IP# changed.
Of course if you're moving out of their data center you can't do that; the purpose of the Internal License is to use inside the data center.
If you bought a server with an internal license installed, then your server vendor can have the IP# changed.
If neither of these two scenarios apply, then the question is How did you get the Internal License, and from whom?
Jeff