Ubuntu – How to add higher video resolution in Ubuntu 10.04 (UNR on EEE1101HA)

UBUNTU 10.10 is out .. and the ASUS 1101HA still won't display 1366×768 on the LCD.
Time to wipe the UBUNTU partition, expand the WIN7 partitions and pass the machine to a windows user..

I picked up an ASUS EEE 1101HA with Windows 7 and installed UBUNTU 10.04 Netbook Remix (dual boot).

Ubuntu runs fine, but it doesn't recognize that the notebook LCD is 1366×768 and thus only offers 1024×768 and 800×600 as monitor resolution.

So .. how can I tell it about that higher resolution?

(Have root pwd & vi, una-bash-ed to use both.. )

UPDATE

there is currently (early May 2010) no video-driver for the Intel GMA500 "Poulsbo"
=> no solution exists for now.

UPDATE II xorg.conf, created with sudo Xorg -configure removed, too long, no feedback

UPDATE III using cvt and xrandr as per adamgmetzler's suggestion (doesn't work)

note that 1366 is not a multiple of 8, so cvt silently 'upgraded' to 1368

lexu@eee1101:~$ cvt 1366 768 60
# 1368x768 59.88 Hz (CVT) hsync: 47.79 kHz; pclk: 85.25 MHz
Modeline "1368x768_60.00"   85.25  1368 1440 1576 1784  768 771 781 798 -hsync +vsync


lexu@eee1101:~$ xrandr --newmode "1368x768_60.00"   85.25  1368 1440 1576 1784  768 771 781 798 -hsync +vsync

lexu@eee1101:~$ xrandr --addmode "default" "1368x768_60.00"

after doing this I can select the new resolution, but get an error message:
could not set configuration for CRTC 262