There's a new version with the corner-scroll feature enabled. It can't be turned off because I can't add features to the Trackpad preference pane. I personally don't like corner-scroll so I'm leaving the old driver there as well; choose the one you want.
This is a port of the Linux Sentelic driver into the ApplePS2Controller.kext. The only functional change over the stock driver is filtering out touchpad-clicks. Only the physical buttons are recognised.
I've written it as an additional class under the ApplePS2Trackpad.kext plugin. When correctly loaded the driver appears in dmesg.
$ sudo dmesg ApplePS2Trackpad: Sentelic FSP 12.0.1
Under 10.5.6 the trackpad preference pane disappears, as does the mouse preference pane, so make sure you have tracking configured the way you like it before installing this driver.
To install simply unpack the driver, then install it into /System/Libraray/Extensions, and reboot.
$ sudo rm -rf /System/Library/Extensions/ApplePS2Controller.kext $ sudo mv ~/Downloads/System/Library/Extensions/ApplePS2Controller.kext /System/Library/Extensions/ $ sudo chmod -R 755 /System/Library/Extensions/ApplePS2Controller.kext $ sudo chown -R root:wheel /System/Library/Extensions/ApplePS2Controller.kext
Tested on an MSI Wind U100. Works correctly after reboots and wake-from-sleep.
NB: the ApplePS2Mouse.kext plugin has been removed from my package because it was taking priority over the trackpad plugin. If anybody knows a better way to set priority, let me know.
UPDATE: Fixed the Trackpad Preference Pane.
CyberGreg said he could control the trackpad with 10.5.5 Keyboard preference pane. With a little fiddling I have achieved a similar result which enables the 10.5.6 Keyboard and Trackpad preference panes with the new Sentelic enabled driver.
First modify the 10.5.6 Trackpad preference pane to disable Apple's vendor ID check. Edit the Info.plist for the Trackpad.prefPane
$ sudo pico /System/Library/PreferencePanes/Trackpad.prefPane/Contents/Info.plist
And remove these lines
Save the file then reboot. Notice that the Trackpad preference pane does *not* yet appear in System Preferences. Next grab the 10.5.5 Keyboard preference pane from here:
Install it using the standard technique but do *not* delete the 10.5.6 Keyboard preference pane
$ sudo mv /System/Library/PreferencePanes/Keyboard.prefPane /System/Library/PreferencePanes/Keyboard.prefPane.10.5.6 $ sudo chmod 000 /System/Library/PreferencePanes/Keyboard.prefPane.10.5.6 $ sudo mv ~/Downloads/Keyboard.prefPane /System/Library/PreferencePanes/ $ sudo chown -R root:wheel /System/Library/PreferencePanes/Keyboard.prefPane $ sudo chmod -R 755 /System/Library/PreferencePanes/Keyboard.prefPane
Reboot. Now you should have both the 10.5.5 Keyboard pane and the 10.5.6 Trackpad pane. On my machine at least, using the 10.5.5 Keyboard pane to configure the trackpad causes System Preferences to crash. Now restore the 10.5.6 Keyboard pane.
$ sudo rm -rf /System/Library/PreferencePanes/Keyboard.prefPane $ sudo mv /System/Library/PreferencePanes/Keyboard.prefPane.10.5.6 /System/Library/PreferencePanes/Keyboard.prefPane $ sudo chmod 755 /System/Library/PreferencePanes/Keyboard.prefPane
Reboot. Now strangely although we have the same files as in the beginning, the Trackpad pane now appears in System Preferences. You can control Tracking Speed and Clicking from this pane. Also you have the 10.5.6 Keyboard pane so there's no loss of functionality.
It's a little bit of mucking about but it's a good result. Thanks CyberGreg.