Dual Head - Primary display

[Dipy]

Hi,
I have a latop, and an external LCD screen which I connect to my laptop using the VGA output (graphic card is an ATI Radeon Mobility X600).
I'm trying to use dual head, but I've got a little problem: it works great (also with different resolutions on both screens), but the 'primary' display (the one kdm is launched on, and the one with my 'standard' desktop) is the external LCD screen. I would like it to be the lcd screen of my laptop instead, because this is the one I will use (the other will be used to dispaly video, web, ...).
I tried many thing in my xorg.conf (such as switching the screen names, ...), but can't get anything to work.

Here is my full xorg.conf:

Section "ServerLayout"
	Identifier     "Default Layout"
	Screen        0 "VGA Screen"
	Screen        1 "LCD Screen" Above "VGA Screen"
	InputDevice    "Touchpad"
	InputDevice    "Keyboard"
	InputDevice    "Mouse"
EndSection

Section "Files"
	FontPath     "/usr/share/fonts/misc:unscaled"
	FontPath     "/usr/share/fonts/Type1"
	FontPath     "/usr/share/fonts/corefonts"
	FontPath     "/usr/share/fonts/freefonts"
	FontPath     "/usr/share/fonts/sharefonts"
	FontPath     "/usr/share/fonts/terminus"
	FontPath     "/usr/share/fonts/ttf-bitstream-vera"
	FontPath     "/usr/share/fonts/unifont"
	FontPath     "/usr/share/fonts/75dpi:unscaled"
	FontPath     "/usr/share/fonts/100dpi:unscaled"
	FontPath     "/usr/share/fonts/artwiz"
EndSection

Section "Module"
	Load  "dbe"
	SubSection "extmod"
		Option	    "omit xfree86-dga"
	EndSubSection
	Load  "freetype"
	Load  "dri"
	Load  "glx"
	Load  "synaptics"
EndSection

Section "ServerFlags"
	Option	    "BlankTime" "5"
	Option	    "StandbyTime" "10"
	Option	    "SuspendTime" "20"
	Option	    "OffTime" "30"
	Option	    "AIGLX" "off"
EndSection

Section "InputDevice"
	Identifier  "Keyboard"
	Driver      "kbd"
	Option	    "CoreKeyboard"
	Option	    "AutoRepeat" "500 30"
	Option	    "XkbRules" "xorg"
	Option	    "XkbModel" "pc105"
	Option	    "XkbLayout" "fr"
	Option	    "XkbVariant" "basic"
	Option	    "XkbOptions" "altwin:super_win"
EndSection

Section "InputDevice"
	Identifier  "Touchpad"
	Driver      "synaptics"
	Option	    "CorePointer"
	Option	    "Device" "/dev/input/mice"
	Option	    "Protocol" "auto-dev"
	Option	    "Emulate3Buttons" "yes"
	Option	    "LeftEdge" "1700"
	Option	    "RightEdge" "5300"
	Option	    "TopEdge" "1700"
	Option	    "BottomEdge" "4200"
	Option	    "FingerLow" "10"
	Option	    "FingerHigh" "20"
	Option	    "MaxTapTime" "180"
	Option	    "MaxTapMove" "220"
	Option	    "VertScrollDelta" "100"
	Option	    "MinSpeed" "0.06"
	Option	    "MaxSpeed" "0.12"
	Option	    "AccelFactor" "0.0010"
	Option	    "SHMConfig" "on"
EndSection

Section "InputDevice"
	Identifier  "Mouse"
	Driver      "mouse"
	Option	    "SendCoreEvents" "on"
	Option	    "Protocol" "Auto"
	Option	    "Device" "/dev/psaux"
	Option	    "Emulate3Buttons" "off"
	Option	    "ZAxisMapping" "4 5"
	Option	    "Resolution" "800"
EndSection

Section "Monitor"

# DisplaySize 433 260
	Identifier   "Laptop Monitor"
	HorizSync    31.5 - 90.0
	VertRefresh  59.0 - 75.0
	Option	    "DPMS" "on"
EndSection

Section "Monitor"
	Identifier   "External Monitor"
	Option	    "DPMS" "on"
	Option	    "ModelName" "Generic Autodetecting Monitor"
EndSection

Section "Device"
	Identifier  "ATI Mobility x600"
	Driver      "fglrx"
	Option	    "FSAAEnable" "off"
	Option	    "VideoOverlay" "on"
	Option	    "Centermode" "on"
	Option	    "PowerState" "1" 
	Option	    "HSync2" "65" 
	Option	    "VRefresh2" "60" 
	Option	    "EnablePrivateBackZ" "yes" 
	Option	    "PairMode" "1280x768+1280x1024" 
	Option	    "Capabilities" "0x00000800"
	Option	    "Mode2" "1280x1024"
	Option	    "ForceMonitors" "lvds"
	Option	    "UseFastTLS" "0"
	Option	    "EnableMonitor" "lvds,auto"
	Option	    "DynamicClocks" "on"
	BusID       "PCI:1:0:0"
EndSection

Section "Device"
	Identifier  "ATI Mobility x600 - Second Device"
	Driver      "fglrx"
	BusID       "PCI:1:0:0"
	Screen      1
EndSection

Section "Screen"
	Identifier "LCD Screen"
	Device     "ATI Mobility x600"
	Monitor    "Laptop Monitor"
	DefaultDepth     24
	SubSection "Display"
		Depth     24
		Modes    "1280x768" "1024x768"
	EndSubSection
EndSection

Section "Screen"
	Identifier "VGA Screen"
	Device     "ATI Mobility x600 - Second Device"
	Monitor    "External Monitor"
	DefaultDepth     24
	SubSection "Display"
		Depth     24
		Modes    "1280x1024" "1024x768"
	EndSubSection
EndSection

Section "DRI"
	Mode         0666
EndSection

Is what I'm trying to do possible (I've seen many person asking the same thing, but with no result)? If yes, how to do it; if no, is there a reason for not allowing it ?

Also, an other question: when using dual head, I can't get to play a video on neither screen: on both it just show a blue window (just like if the overlay was on the other screen). What option do I need to add to my device configuration to be able to play a video on at least one screen ?


Thanks