[NTG-context] setupheads separator and stopper

Hello list members: contextgarden wiki site http://wiki.contextgarden.net/Command/setupheads says that the \setupheads command "has been reported non-working for some people". For me the alternative=inmargin/normal options work, but the separator= and stopper= options have no effect. I would like my chapter, section etc numbers to have a dot after them, eg 1. 1.1. etc. How could I achieve this? Just in curiousity, how can I change the separator? Thanks in advance, bcsikos