Hi guys!
I have reintalled Virtualbox from the previous version to the 4.2.0. Guest additions should be automatically installed in this version. I am trying to share (as I was able to do before) a folder from my 11.10 ubuntu OS guest to a windows xp OS. I have added the folder as shared from Virtualbox. I am trying now to do the following
lollo@mangusta:~$ sudo mount -t vboxsf condivisa  /media/vbox_condivisa -o uid=`id -u`,gid=`id -g`
mount: tipo di filesystem 'vboxsf' sconosciuto
So basically vboxsf is not recognized. In ubuntu help it is suggested to change vboxsf to vboxfs but it doesn't change anything. If I continue the procedure with
net use x: \\vboxsvr\share

But obviously it doesn't work.
Any suggestions?

Thank you very much!