[TYPO3-mvc] f:translate don't works in backend

[Stefan Frömken]

Hello,

I'm just programming my first BE-Extension. It very easy now. Thx.

My last step to finish this extension is to translate my hardcoded texts 
in fluid-template.
My Problem: It works with english, but it don't works with german or 
other installed languages.
My BE-User is set to german, but the lables are still in english.

I have just installed your blog_example and I have the same problem 
there in TYPO3 4.6.0Alpha2.

And ideas?

Stefan