If the powers that be turned round and said we all need to speak french (or any other language) then so be it. I wouldn't complain. The point is that while there are 5 allowed languages then there will always be incidents.
I was talking to a french pilot about this subject last week and he said that if you fly into an airport in an ICAO country then you can speak in any of the 5 languages and they must provide a controller that can speak it back to you. I told him he was talking rubbish but it made me think about it so I'm going to go check it out.
radar707, you had better get a subscription to linguaphone because I'm gonna be testing you soon!