What is content of your /var/log/Xorg.0.log and /etc/X11/xorg.conf ?
Do you have hal installed and running ?
Without hal, you might need to specify in your xorg.conf,
using something like:
Section "ServerLayout"
InputDevice "Generic Keyboard"
InputDevice "Configured Mouse"
Option "AutoAddDevices" "off"
EndSection
Section "InputDevice"
Identifier "Generic Keyboard"
Driver "kbd"
Option "CoreKeyboard"
Option "XkbRules" "xorg"
Option "XkbModel" "pc104"
Option "XkbLayout" "us,cz"
Option "XkbVariant" ",qwerty"
Option "XkbOptions" "grp:shift_toggle,grp_led:scroll"
EndSection
Section "InputDevice"
Identifier "Configured Mouse"
Driver "mouse"
Option "CorePointer"
Option "Device" "/dev/ums0"
# Option "Device" "/dev/psm0"
Option "Protocol" "auto"
Option "Emulate3Buttons" "true"
EndSection