[TYPO3-english] Problem with backend interface

[Elvio G.]

Hi.
I have a problem with backend interface on extension manager.
With the last Typo3 4.7.1. and Xampp on windows 7.
Blank and fresh install. After Updated Italian language, under user 
settings, i changed my default language to Italian.
Now, i see this:

http://i49.tinypic.com/9i8uj9.png

Value of menu tab and button have disappeared...
Any idea?

Thank you :)

Elvio G.