This change (from 2.4.18rc2-ac2):
o Improve handling of psaux open with no mouse present (Christoph Hellwig)
breaks the handling of the case where there is a PS/2 mouse
and no PS/2 keyboard (for example, USB keyboard.) In this
situation, the first time /dev/psaux is opened, it will return
-ENXIO. Subsequent opens appear to act normal.
Bill