Win32 nsupdate.exe variable expansion

[Raymond]

Utilizing Win32 version of Bind9 nsupdate.exe to push Win2K/XP client rr's to 
a Linux hosted Bind9.

Would like to use Win32 system variables such as COMPUTERNAME and a couple of 
other application specific system vars in the nsupdate configuration script 
for a generic configuration. 

How does one utilize Windows environment and system vars within the nsupdate 
configuration file.

Attempted update add %COMPUTERNAME%.<dns suffix> <ttl> <class> <type> <data>
but a literal '%COMPUTERNAME%' is added with no variable expansion. Also 
attempted *nix shell style $<varname> and ${<varname>}, to no avail.

Help please
-- 
Raymond