retaining use of the mouse wheel with "psmouse_noext=1"?

[Greg Norris <haphazard@kc.rr.com>]

I have to use the "psmouse_noext=1" option to psmouse.ko, in order to
keep the pointer from going stark-raving mad[1] when I use my KVM
switch.  Unfortunately, this seems to squash the use of the mouse wheel
for scrolling (it still works as a 3rd button), which is a feature I'd
really like to retain.  Is there any way to keep the wheel fully
functional when using this option (or otherwise fix the KVM issue)? 
It's a Belkin SOHO 4-port switch, if that makes a difference.


[1] The mouse pointer jumps wildly around the screen at the slightest
nudge, while simultaneously doing a cut/paste of every bit of text in
sight.  The only way to reset things to normal seems to be an
unload/reload of the psmouse module.