The TclX copyright states the following.
Copyright 1992-1996 Karl Lehenbauer and Mark Diekhans. Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies. Karl Lehenbauer and Mark Diekhans make no representations about the suitability of this software for any purpose. It is provided "as is" without express or implied warranty.