The U.K.’s Ministry of Justice boosts database performance and strengthens security of National Offender Database by moving to Oracle Database 11g.

Read more about how they did it and why they did it in the  success story:
http://www.ukocn.com/files/case-studies/Ministry%20Of%20Justice%2011g%20Upgrade%20and%20Options%20Case%20Study.pdf

You can do it as well 🙂