I have a new (old) MacBooc Pro 3.1 4GB
I installed virtualbox and tried to install ubutntu 9.10 but it went wrong. The graphic part of the installer was all garbage. So I went to 9.04.
I installed the guest_additions.
The resolution of my external monitor went bad one or two times and I needed to set it manually even after the guest additions installation. But now it works ok with different monitors and resolutions.
There are some issues with the shared folders. I don’t know if the problem with having capital letters in the shared folder still apply but the other common problem with s.f. (That I hit several times in this installation) is to try to mount from the folder where the mount points are:
/sbin/mount.vboxsf: mounting failed with the error: Protocol error
If you try to mount the folder from the directory where the mount point are:
ej, you are in /sf and your mount points are /sf/software /sf/tmp /sf/mac_home etc
/sf$ sudo mount -t vboxsf -o uid=1000,gid=1000 sf_software /sf/software/
Went to ~/home and tried from there and all went ok
PD: I took me a lot of blog-reading to find this solution. Hope it helps!