Option “ZAxisMapping” “4 5″

これを削除して、

Option “XAxisMapping” “6 7″
Option “YAxisMapping” “4 5″
Option “EmulateWheelTimeOut” “200″

を追加します。
それから、firefox横スクロールはabout:configで

mousewheel.horizscroll.withnokey.action = 0
mousewheel.horizscroll.withnokey.numlines = 1
mousewheel.horizscroll.withnokey.sysnumlines = true

にそれぞれ変更します。
今のxorg.confはここに置きます。

1 インストール直後のxorg.conf

2 atiアクセラレーション有効のxorg.conf

3 radeonアクセラレーション有効のxorg.conf

1はともかく、Google Earthは3のradeonで動くそうです。
こちらのサイトにありました。感謝！

ファイルの内容は次のとおりです・・・

Section “Files”
FontPath “/usr/share/fonts/X11/misc”
FontPath “/usr/share/fonts/X11/cyrillic”
FontPath “/usr/share/fonts/X11/100dpi/:unscaled”
FontPath “/usr/share/fonts/X11/75dpi/:unscaled”
FontPath “/usr/share/fonts/X11/Type1″
FontPath “/usr/share/fonts/X11/100dpi”
FontPath “/usr/share/fonts/X11/75dpi”
# path to defoma fonts
FontPath “/var/lib/defoma/x-ttcidfont-conf.d/dirs/TrueType”
EndSection

Section “Module”
Load “i2c”
Load “bitmap”
Load “ddc”
Load “dri”
Load “extmod”
Load “freetype”
Load “glx”
Load “int10″
Load “vbe”
EndSection

Section “InputDevice”
Identifier “Generic Keyboard”
Driver “kbd”
Option “CoreKeyboard”
Option “XkbRules” “xorg”
Option “XkbModel” “jp106″
Option “XkbLayout” “jp,jp”
Option “XkbVariant” “latin,”
Option “XkbOptions” “grp:alt_shift_toggle,grp_led:scroll”
EndSection

Section “InputDevice”
Identifier “Configured Mouse”
Driver “mouse”
Option “CorePointer”
Option “Device” “/dev/input/mice”
Option “Protocol” “ImPS/2″
Option “ZAxisMapping” “4 5″
Option “Emulate3Buttons” “true”
Option “EmulateWheel” “true”
Option “EmulateWheelButton” “2″
EndSection

Section “InputDevice”
Identifier “Synaptics Touchpad”
Driver “synaptics”
Option “SendCoreEvents” “true”
Option “Device” “/dev/psaux”
Option “Protocol” “auto-dev”
Option “HorizScrollDelta” “0″
EndSection

Section “InputDevice”
Driver “wacom”
Identifier “stylus”
Option “Device” “/dev/input/wacom”
Option “Type” “stylus”
Option “ForceDevice” “ISDV4″ # Tablet PC ONLY
EndSection

Section “InputDevice”
Driver “wacom”
Identifier “eraser”
Option “Device” “/dev/input/wacom”
Option “Type” “eraser”
Option “ForceDevice” “ISDV4″ # Tablet PC ONLY
EndSection

Section “InputDevice”
Driver “wacom”
Identifier “cursor”
Option “Device” “/dev/input/wacom”
Option “Type” “cursor”
Option “ForceDevice” “ISDV4″ # Tablet PC ONLY
EndSection

Section “Device”
Identifier “ATI Technologies Inc Radeon Mobility M6 LY”
Driver “ati”
BusID “PCI:1:0:0″
Option “BusType” “PCI”
Option “AGPMode” “4″
Option “AGPSize” “32″ # default: 8
Option “AGPFastWrite” “false” # More stable this way.
Option “SWcursor” “true” # More stable this way.
Option “EnablePageFlip” “true” # Faster.
Option “EnableDepthMoves” “false” # More stable this way.
Option “RenderAccel” “false” # More stable this way
Option “AccelMethod” “XAA” # or XAA, EXA, XAA more stable
Option “DDCMode”
Option “SubPixelOrder” “NONE”
Option “ColorTiling” “false” # More stable this way.
Option “DynamicClocks” “true”
Option “bioshotkeys” “True”
Option “XAANoOffscreenPixmaps” “true”
EndSection

Section “Monitor”
Identifier “Generic Monitor”
Option “DPMS”
EndSection

Section “Screen”
Identifier “Default Screen”
Device “ATI Technologies Inc Radeon Mobility M6 LY”
Monitor “Generic Monitor”
DefaultDepth 24
SubSection “Display”
Depth 1
Modes “1024×768″
EndSubSection
SubSection “Display”
Depth 4
Modes “1024×768″
EndSubSection
SubSection “Display”
Depth 8
Modes “1024×768″
EndSubSection
SubSection “Display”
Depth 15
Modes “1024×768″
EndSubSection
SubSection “Display”
Depth 16
Modes “1024×768″
EndSubSection
SubSection “Display”
Depth 24
Modes “1024×768″
EndSubSection
EndSection

Section “ServerLayout”
Identifier “Default Layout”
Screen “Default Screen”
InputDevice “Generic Keyboard”
InputDevice “Configured Mouse”
InputDevice “stylus” “SendCoreEvents”
InputDevice “cursor” “SendCoreEvents”
InputDevice “eraser” “SendCoreEvents”
InputDevice “Synaptics Touchpad”
EndSection

Section “DRI”
Mode 0666
EndSection