From the Microsofts Terminal Services FAQ at
http://www.microsoft.com/windowsserver2003/community/centers/terminal/termi
nal_faq.asp
Q. How do I move my licenses from one licensing server to another?
A. You should back up your Terminal Services licensing server regularly by
using the Windows Backup tool or similar. This will help protect your
licensing data from accidental loss if your system experiences hardware or
storage failure.
When backing up a Terminal Server License Server, back up both the System
State data and the folder in which the Terminal Server License Server is
installed. This ensures that data in both the registry and the Terminal
Services licensing server database is backed up.
If you restore the System State data and the database to the original
Terminal Services licensing server computer, any unissued licenses are
restored correctly as long as you have not replaced the operating system on
the computer. Otherwise any unissued licenses are not restored and an event
will appear in the system log providing the unissued count. You can still
restore the unissued licenses by using the TS License Manager tool with the
Telephone activation mechanism, and requesting the licenses back. You can
switch to the Telephone mechanism by right clicking on the server in TS
License Manager, and selecting properties from the menu.