SOLUTION !

A week is all it has taken to find how to tell (expletive deleted) X to resume recognizing my pc101 PS/2 keyboard in my Knoppix/Debian setup. As best I can gather, physically removing my PS/2 mouse changed the description of the keyboard to 105. But switching the description back to 101 in XFConfig-4 was not good enough...the line describing the mouse also had to be commented out. Then X resumed recognizing the keyboard.
Thanks to Christopher (aka franknputer) and lordarkan whose solutions were found in this fascinating string.
<http://www.mepis.org/node/view/335>
chada