[NTG-context] No indicators in registers when using french as main language

Hello, The subject says it all. \mainlanguage[fr] \starttext \index{Item}Item \placeindex \stoptext There is no indicator "i" in the index. It appears when you comment out the first line or change it to another language. Adding \setupregister[index][indicator=yes] does not help. Another, probably unrelated, problem is that \completeindex does not seem to do anything. Vianney