VNC freezes intermittantly

[Bryan Buus]

I'm running VNC 4 client on a XP Pro box and VNC 4 server on a Fedora Core 2
machine.  These machines are on the same wireless lan.  VNC connects just
fine and seems to work ok for a while (anywhere from 5 minutes to an hour),
but then intermittantly "freezes" -- I know that the machine is alive,
pingable, etc (I can be logged in via ssh at the same time and work in the
shell).  Control will return after a few minutes.  This behavior happens
both on the vnc embedded into X, and on a vncserver that I start myself.
Typically closing the vnc client and restarting/reconnecting re-establishes
control.

With logging turned on, the only thing that the server reports are messages
like the following:
  XserverDesktop: keycode 39 down
  XserverDesktop: keycode 32 down

Any ideas what might cause this problem?

Bryan