Thanks Cheater!
Excellent suggestion.
Of course it does not work when connected to the PS/2 port either.
I have searched the internets for hints on hooking this particular model (TM41PDD219-1) up and have found nothing.
I did find excellent references for other models, but this one does not appear to be documented.
If anyone is in need of Synaptics literature it is available on their web site (http://www.synaptics.com/support/dev_support.cfm).
I suppose I will keep hunting...