RHEL4下鼠标问题

sbysky

鼠标型号是NEC的M909光电鼠标，鼠标刚开始装完系统还是好的，没过几天突然失效了，/etx/X11/xorg设置是：

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

请教解决办法，多谢了