Yes, that's no problem. You'll have to install them as Per Device
TS CALs, since W2K doesn't know what a Per User TS CAL is.
From:
Windows Server 2003 Terminal Server Licensing White paper
http://www.microsoft.com/windowsserver2003/techinfo/overview/terms
ervlic.mspx
<quote>
Prevent License Upgrade Policy
Computer Configuration/Administrative Templates/Windows
Components/Terminal Services/Licensing
A license server attempts to provide the most appropriate Client
Access License (CAL) for a connection. For example, a license
server provides a Windows 2000 TS CAL token for clients connecting
to a terminal server running Windows 2000 and a Windows Server
2003 Family Per Device TS CAL token for a connection to a terminal
server running Windows Server 2003.
By default, this per-computer setting allows a license server to
supply a Windows Server 2003 Family Device TS CAL token, if
available, to a terminal server running Windows 2000 if there are
no Windows 2000 TS CAL tokens available.
If the status is set to Enabled, when a terminal server running
Windows 2000 requests a license, but no Windows 2000 TS CAL token
is available, a temporary CAL is issued if the client has not
already been issued a temporary CAL. Otherwise, no CAL is issued
and the client is refused connection, unless the terminal server
is within its grace period.
Note that this policy only applies to Device CAL tokens, as there
is only one version of User CAL tokens.
</quote>
