Hmm, I have not run into this. I presume you have an account? Just an aside, but have you tried using TubeMate? It is a very handy app that allows you to either view or save YouTube videos and gives you saving options. May want to give it a try.
+1 to Youtube mate! I found it in the app market and its free! I use it for saving videos that I think. But I ask this. Why not just use the web site if you wanna just view the videos?