Streaming video from youtube

[Davide]

Hi, I'm new about VLC and Linux and i have a problem.
I have Ubuntu on a virtual machine and it connects to youtube correctly. I'm also trying to see a video in streaming from youtube with VLC: in VLC i set the URL of the video i'm trying to see but it gives me the error: "VLC can't open the MRL http://youtube.com/.... see the register for more detail".

Can anyone help me?? maybe i have to set or install something???
Thanks a lot