In order to use facebook in other language you need the translation application from http://www.facebook.com/translations/index.php?app=1
Beside translating into other languages like bengali, hindi, french there are two funny translations; upside down english and pirate english ! I didn’t know about it before until I looked through all the languages in the translation menu located at the footer of the facebook page.
Facebook in action with upside down english:

Facebook in action with pirate english:




