[NTG-context] Problem with \c{a}

Dear list, I cannot get \c{a} to work in mkiv. Small test file: \starttext \c{c} % works both in mkii and mkiv \c{a} % works only in mkii (in mkiv I get nothing) \stoptext Is there a fix for this? I would not like to use the unicode char directly in the file (because I have this inside a bib-entry and I'd like to keep the bib file without such constructions.) Best regards, Mikael