It should work as normal.
What OS are you running and does it occur in all apps that you try it in?
On a side note - I'm guess you are aware that the Ctrl key on the right hand side of the keyboard is used by VBox for some default Shortcuts?
Edit - this can be changed if you so wish
Well, it doesn't work in Word, Wordpad, Firefox nor IE, so I assume that there's a basic problem somewhere. That's using the left
CTRL-key, BTW. The command Edit -> Paste works, so its not a clipboard problem.
And, I'm running gnome_2010.12.
Thanks for your help