Elton Woo stated :
Section "InputDevice" # If the normal CorePointer mouse is not a USB mouse then # this input device can be used in AlwaysCore mode to let you # also use USB mice at the same time. Identifier "DevInputMice" Driver "mouse" Option "Protocol" "IMPS/2" Option "Device" "/dev/input/mice" Option "ZAxisMapping" "4 5" Option "Emulate3Buttons" "no" EndSection .......
... it sounds a bit strange that the new kernel would mess up scrolling, so this is the first thing I would check.
My XF86Config hasn't changed in all the iterations of 2.6.0-1. kernels nor the 2.4.22. kernels I've tested and used. So this section of XF86Config is exactly as you pointed out. The interesting thing here is that if I load kernel 2.4.22-1.2135.nptl my mouse scrolls very nicely. Not sure what else to look at.
Please follow up with some other action I could experiment with.
All the best.
RaXeT