Spoofing an app under Win2K/NT4.0

I have an app that runs under NT4.0 that originally was written to insure that users did not attempt to run it under Win9x by checking the OS. I am now upgrading to Win2K Advanced Server and the original app is not available for Win2K. Does anyoneknow how to spoof the app to believe it is running under NT? In “olden times” DOS solved the problem with an entry in config.sys.
Thanks Jack