[NTG-context] definetypeface confusion

Hi there, I am a bit confused about \definetypeface. I try to mix some self-installed otf-fonts. Serif works fine, but I can't get the sans variant to work: \definetypeface [chaparral][rm][serif] [chaparral][default][encoding=texnansi] \definetypeface [myriad] [ss][sans] [myriad] [default][encoding=texnansi] \ss does not switch to myriad (instead, ConTeXt uses lmss), but \myriad does! So I think that the font is installed correctly and the typescript is not completely broken. How should the \setupbodyfont look like? My current setup is: \setupbodyfont[chaparral,14pt] What other information do you need? Patrick