[NTG-context] math: `\ref` does not work for referencing formulae (ConTeXt ver: 2011.06.19)

Dear ConTeXt folks, using ConTeXt ver: 2011.06.19 14:17 MKIV fmt: 2011.6.21 int: english/english the following minimal example taken from the Wiki page [1] does not work as expected. --- 8< --- minimal example --- >8 --- \starttext The famous result (and again) is given by \placeformula[formulalabel] \startformula c^2 = a^2 + b^2. \stopformula And now we can refer to formula \ref[formulalabel] (ref). And now we can refer to formula \in[formulalabel] (in). \stoptext --- 8< --- minimal example --- >8 --- `\ref` does not seem to find the label for the equation. `\in` does work. Thanks, Paul [1] http://wiki.contextgarden.net/Math/Display#Referencing_formulae