It is possible to specify a preferred TS License Server with Group Policy for Windows Server 2003 with Service Pack 1. Here is the procedure for setting the preferred TS License Server for 2000/2003 without using group policy:

Windows 2000:
http://support.microsoft.com/kb/239107
To select a specific license server, locate the following key in the registry:
HKLM\SYSTEM\CCSServices\TermService\Parameters
Add the following value:
Name: DefaultLicenseServer
Data type: REG_SZ
Data value: ServerName
Substitute the NetBIOS name of the appropriate license server for ServerName. If the license server is located on a remote subnet, make sure the Terminal Services-based computer can resolve the NetBIOS name.

Windows Server 2003:
http://support.microsoft.com/kb/279561
To select a specific license server, follow these steps, and then quit Registry Editor.

1. Click Start, click Run, type regedit, and then click OK.
2. Locate and then click the following key in the registry:
   HKLM\SYSTEM\CCS\Services\TermService\Parameters
3. On the Edit menu, point to New, and then click Key.
4. Name the new key “LicenseServers”
5. Locate and then click the following key in the registry:
   HKLM\SYSTEM\CCS\Services\TermService\Parameters\LicenseServers
6. For each licensing server to which you would like to point the Terminal Services server, point to New on the Edit menu, and then click Key.
7. Name the new key “ServerName” where ServerName is the NetBIOS name of the license server that you want to use, and then press ENTER.
   Note The new key name can be any of the following designations that represent the license server:
   • The NetBIOS name of the server
   • The fully qualified domain name (FQDN) of the server
   • The IP Address of the server
8. Restart your computer.