It does sound like X is not finding your mouse.

Or rather, that NetBSD isn't.  X is probably happy since X is using
/dev/wsmouse or /dev/wsmouse[0-9]* for its mouse input.  Especially
for /dev/wsmouse (which can be a multiplex of mice rather than just
1 mouse), X may be satisfactorily opening the /dev special file even
though there is no OS level device.

Some suggestions:

 * Check your X config.  Whatever device X is told to open for
   the mouse, try (outside of X, perhaps as root):

     od /dev/wsmouse      ; Or whatever

   ...and move the mouse & click buttons.

   If you see no output coming out of this, then NetBSD isn't
   reporting anything where you have told X to look.  If you
   do see output, and you're doubly-sure that X is using the
   same device, then X is probably failing to interpret the
   protocol.

 * Check that X is using the "wsmouse" protocol.  I recall that
   in the past, XFree86 would detect /dev/wsmouse, but bizarrely
   would use a PS/2 protocol or some such, if left to its auto-
   config support.  The wsmouse devices use an abstract protocol,
   rather than reporting raw bits from the mouse, so that it does
   not matter what physical mouse you have as long as wsmouse
   understands it.  (This suggests a possibility that wsmouse may
   not understand your mouse...(^&)

 * Try a USB mouse?  I've gone over to USB for mice and keyboards
   for the most part and have little problem with these.

 * If the mouse is a USB mouse, is it directly plugged into the
   system?  Or did you get an extra hub?  (I seem to recall
   having some trouble with a hub plugged into USB port in
   the past.)

 * Double-check that your mouse is firmly plugged in.

 * If using PS/2 mice, double-check that the mouse is in the mouse
   port, not the keyboard port.  The two are apparently different,
   though physically they have the same connectors.

 * If you only have one PS/2 port, double-check that it's a mouse
   port, not a keyboard port.  My laptop has one PS/2 port only for
   a keyboard, I believe; a mouse must either be serial or USB for
   that machine.

 * As a last resort, you might plug the working mouse from the older
   system into the newer system.  (If you haven't already tried that.)


I hope that one or more of those suggestions is of some help to
you.  (^&

Good luck.

-- 
  "I probably don't know what I'm talking about."  http://www.olib.org/~rkr/