A clarification.  Earlier I made the following comment:

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I just brought up NetBSD 1.0 with the XF86 3.1 binaries from the Walnut
Creek NetBSD/FreeBSD CDROM, and have had no troubles with the XF stuff
of the kind you describe.  My platforms are 486DX4s/8M ram clones, with
Cirrus 5424 clone controller.  The middle button on the "three button 
Microsoft mouse" does not work, but other than that things are working
very well.
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I have determined that my mice are simply odd beasts; none of the normal
incantations will make the middle mouse button transmit anything.  They
will not work with the MouseSystems driver, even with the (ClearDTR, ClearRTS)
functions.  I don't think this is XF86's fault, so I have to claim that I
am having no problems at all with XF 3.1.  My SVGA server claims to
be 3.1PL0, although it may not have been affected by the patches.

--Terry Moore
Databook Inc.