Sometimes you need to remove a package from your System, this is the way.
First discover the packages which are bothering you:
dpkg -l | grep ruby
Once you catched them, purge them from the system (removing binaries and configuration files):
sudo dpkg -P libruby1.8
Someone from developers of vBox needs some ass kick serulisoy ! I have heard a lot how vBox is state of the art free virtualization app and how everything is great and works ! In reality nothing but headaches and problems for things that should works out from the box !!! I don’t care that is free in fact with free software one has even more problems like free software free problems the more the freedom the more the problems ! Nothing seems to work as promised advertised network problems guest appliance not installing no network adapter in guests and so on !!! What they are doing ? Inventing how to bring user nerves sky high or what ??? If they can’t do it properly they should packs the bags and go raise vegetables and leave open source to handle it ! I’m pretty sure that such glitches under open source community would not be tolerated in long term and will be fixed pretty soon !!! But today we are losing nerves on crappy coding !!!