screen resolution for k/ubuntu 8.0.4 hardy heron running on virtualbox

Just fixed a resolution issue for my ubuntu hardy heron guest system running in virtual box (host is kubuntu 8.0.4). The solution is based on this thread.

There are two things I changed in xorg.conf to make it work:

1. find the video driver device second and add Driver "vboxvideo". see following:
   

   Section "Device"
    Identifier "Configured Video Device"
    Driver "vboxvideo"
   EndSection

   
   
2. find the screen section and add a display subsection including the modes.
   

   Section "Screen"
    Identifier    "Default Screen"
    Monitor        "Configured Monitor"
    Device        "Configured Video Device"
    SubSection    "Display"
        Modes "1280x800" "1024x768" "800x600"
    EndSubSection
   EndSection

Voila! it works. The only drawback is that the auto-resize guest display function of virtual box doesn't work.