[NTG-context] \sharp and \flat are not displayed

Hi, In the beta, I cannot get \sharp and \flat signs after font setup. What should I do to get them back? Minimal example: \starttypescript [serif] [MinionPro] \definefontsynonym [Serif][MinionPro-Cn.otf][features=default] \stoptypescript \starttypescript [MinionPro] \definetypeface [MinionPro][rm][serif][MinionPro][default] \stoptypescript \usetypescript[MinionPro] \setupbodyfont[MinionPro,16pt] \starttext \sharp \flat \stoptext