#use hwinfo to find out the mode number for your choice of resolution
sudo apt-get install hwinfo
sudo hwinfo --framebuffer | grep 1440x900

#scroll to the end of /boot/grub/menu.lst
#add ‘vga=SOME_MODE_NUMBER’ to the end of the ‘kernel’ line
kernel /boot/vmlinuz-2.6.15-26-server root=/dev/hda1 ro quiet splash vga=0x0336

#reboot into new config
sudo shutdown -r now