I'd like to add a point to FredT's reply.
At
BMA, all general aviation pilots speak Swedish (well the swedish ones that is...) Also, flying at ESGP (near the Norwegian border) I heard Norwegians in the pattern talking Norwegian with Swedish ATC. Now, that is even worse!
(no offense, it is a beautiful language!)
Since there are numerous bizjets and so forth coming in to
BMA from heaven knows where, I agree with FredT, it should be common sense and it sure is a potential safety hazard.
regards,
johan