FC1->FC3: USB mouse + mousewheel no longer working

Hello,

this morning, I upgraded from Fedora Core 1 to Fedora Core 3.
My mouse is no longer working.

I have a Microsoft 2-button USB Wheel mouse. With 'system-config-mouse',
I selected "Generic - Wheel Mouse (USB)". /etc/sysconfig/mouse reads:

FULLNAME="Generic - Wheel Mouse (USB)"
MOUSETYPE="imps2"
XEMU3="no"
XMOUSETYPE="IMPS/2"
DEVICE=/dev/input/mice

On FC1, it was the same, except for DEVICE=/dev/psaux.

The relevant part of /etc/X11/xorg.conf reads:

Section "ServerLayout"
	Identifier     "Default Layout"
	Screen      0  "Screen0" 0 0
	InputDevice    "Mouse0" "CorePointer"
	InputDevice    "Keyboard0" "CoreKeyboard"
	InputDevice    "DevInputMice" "AlwaysCore"
EndSection

Section "Files"

(...)

Section "InputDevice"
	Identifier  "Mouse0"
	Driver      "mouse"
	Option	    "Protocol" "IMPS/2"
	Option	    "Device" "/dev/psaux"
	Option	    "ZAxisMapping" "4 5"
	Option	    "Emulate3Buttons" "no"
EndSection

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

(...)

In FC1's XF86config, this is exactly the same.

The relevant lines of /var/log/messages on boot are:

Nov 29 16:30:28 topjaklont kernel: mice: PS/2 mouse device common for all mice
Nov 29 16:30:28 topjaklont kernel: input: ImPS/2 Generic Wheel Mouse on isa0060/serio1

I tried several different configurations. None of them worked. I can
start X, I see a mouse cursor, but moving the mouse does not move the
mouse cursor.

Any hints? With XFree86 on FC1, it worked fine. It doesn't now :-(

regards,
Gerrit Holl.

P.S.
I am running the same kernel configuration, only recompiled.

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