[NTG-context] \mathextensible{"21FE}

Dear all, The following example doesn't work for me: \setupbodyfont[xits] \starttext \math{x\mathextensible{"2194}{hello}{}y} \math{x\mathextensible{"21FE}{hello}{}y} \math{\char"21FE} \stoptext I found the symbol which I needed there: http://en.wikipedia.org/wiki/Arrow_%28symbol%29#Arrows_in_Unicode and there: http://milde.users.sourceforge.net/LUCR/Math/unimathcmds.pdf Kind regards, Chris