Ubuntu resolution in VirtualBox - revisited

Apparently it isn't enough to install the guest additions in order to get a proper resolution in Ubuntu under VirtualBox. A further necessary step is to use the vboxmanage tool (from the command line) to adjust the resolution as follows:

vboxmanage setextradata "VMname" CustomVideoMode1 AxBxC

where OSname is the name of your virtual machine as it appears in VirtualBox, AxB is your resolution, and C is your colour depth. For example, the command to adjust the resolution on my laptop is:

vboxmanage setextradata "Ubuntu 10.04 LTS i386" CustomVideoMode1 1366x768x32