Restoring mouse integration to Ubuntu guest

For some reason, an Ubuntu 8.10 guest on VirtualBox do not have any mouse integration, even after installing the VirtualBox addons. This is strange because previous versions of Ubuntu I've used have not had this problem.

Anyway, the fix is rather simple. Just modify /etc/X11/xorg.conf by adding the following lines:

Section "InputDevice"
Identifier "Configured Mouse"
Driver "vboxmouse"
Option "CorePointer"

Then, reboot.