the 'two' arduino's are connected by air..
Well, there's your problem. The Arduino's a no good at transmitting data by air.
i added a LED on d13 wich flips state on reciving data, but sadly the power led never goes LOW. (this is the UNO on breadbord)
The power LED on what? Why would you want the power LED to turn off?
did my post sink in all other posts without notice, or does nobody have a clue what could be wrong here?
You are not answering questions correctly, or are giving incomplete answers. It is hard to help you when you do that.