[NTG-context] language not working in transliteration?

Dear list, I have the following sample: \mainlanguage[it] \starttext \usetransliteration[serbian] \definetransliteration [MySerbian] [color=red, language=de, vector={serbian to latin}] \definetransliteration [MySerbianX] [MySerbian] [color=blue] \transliterationexception[serbian to latin] {whatever}{(\currentlanguage): } \starttransliteration[MySerbian]% whatever А \stoptransliteration \transliteration[MySerbianX]{whatever А} \stoptext In both cases, current language is main language (in the sample above, "it" instead of "de"). Am I missing something here? (Sample adapted from lang-tra.mkxl.) Many thanks for your help, Pablo