[NTG-context] funny letters in (type)buffer

Good evening, \enableregime [il1] \starttext \startbuffer funny letters: Ä ü ß \stopbuffer \typebuffer \stoptext gives me in test-test.tmp buffer: funny letters: ^^c4 ^^fc ^^df and this is also typeset like above. Is it possible to get the real letters back without manually editing the written buffer? Patrick