Comment 3 for bug 694222

Xorg starts with defaults (no xorg.conf). The related section in Xorg log looks like this:

[ 3.545] (II) config/udev: Adding input device PS/2 Logitech Wheel Mouse (/dev/input/event8)
[ 3.545] (**) PS/2 Logitech Wheel Mouse: Applying InputClass "evdev pointer catchall"
[ 3.545] (**) PS/2 Logitech Wheel Mouse: always reports core events
[ 3.545] (**) PS/2 Logitech Wheel Mouse: Device: "/dev/input/event8"
[ 3.560] (II) PS/2 Logitech Wheel Mouse: Found 3 mouse buttons
[ 3.560] (II) PS/2 Logitech Wheel Mouse: Found scroll wheel(s)
[ 3.560] (II) PS/2 Logitech Wheel Mouse: Found relative axes
[ 3.560] (II) PS/2 Logitech Wheel Mouse: Found x and y relative axes
[ 3.560] (II) PS/2 Logitech Wheel Mouse: Configuring as mouse
[ 3.560] (**) PS/2 Logitech Wheel Mouse: YAxisMapping: buttons 4 and 5
[ 3.560] (**) PS/2 Logitech Wheel Mouse: EmulateWheelButton: 4, EmulateWheelInertia: 10, EmulateWheelTimeout: 200
[ 3.560] (II) XINPUT: Adding extended input device "PS/2 Logitech Wheel Mouse" (type: MOUSE)
[ 3.560] (II) PS/2 Logitech Wheel Mouse: initialized for relative axes.
[ 3.560] (II) config/udev: Adding input device PS/2 Logitech Wheel Mouse (/dev/input/mouse0)