Edited post, see further elaboration below. Apologies.
There is a way to make Linux autodetect wheel mice in the PS/2 port (which Knoppix currently can't do). The solution is a program called gpm. Unfortunately there is a bug in the current version of gpm (1.20.1) so it doesn't work yet. There will be a new release of gpm in the fall where this is fixed, so the next Knoppix release could incorporate this very important convenience feature.
Anyhow, here's how to do it:
- install gpm and give it the following parameters
input port: /dev/psaux
type: imps2 (so gpm does its autodetection magic)
replication type: imps2 (any other setting will not work)
- in xf86config set the following
"device" should be "/dev/gpmdata" instead of "/dev/psaux"
"protocol" should be "ImPS/2"
zaxismapping and the rest should naturally also be set properly
That's it. I have a self-modified gpm executable with these settings on my laptop and it works great. When I boot without an external PS2 mouse the "knob" works automatically. When I boot with a wheel mouse, scrolling works without any problems.
More information can be found here. X.org's xserver might do proper mouse autodetection in the future, which would eliminate the need to use gpm.
Edited post, see further elaboration below. Apologies.
mine works aswell. BUT not my OPTICAL wheelmouse...
I shold elaborate a bit more on my wheelmouse. It is a Microsoft optical USB wheelmouse with a PS2 adapter. It works flawlessly when running with kernel 2.4.26 hdd install and live CD, however, does not work correctly when running 2.6.6. When running kernel 2.6.6, the scroll wheel does not work and when KDM starts, I have to vigorously move the mouse before it functions at all.Originally Posted by OErjan
I tried this again after a long while, and my wheel mouse was also detected properly, the wheel worked and so on. The Knoppix HW FAQ says that wheelmice are not autodetected. Maybe it is not up to date.

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