Yes, but pay attention: you must press
ctrl+u in order to do that, not
ctrl+U.
So, after pressing
shift for example, and then
ctrl, you must go back to
lowercase letters before pressing
u
Summarizing, you must press: shift - ctrl - shift , then u
Other commands, like Ctrl+d for example, may work in both forms (uppercase and lowercase).
Thank you for pointing this out!!