[NTG-context] Error while loading chemml

Hello, Loading the chemml module I get the following error: system : macros of module chemml loaded (/usr/share/texmf-tetex/tex/context/base/x-chemml.tex xml : loading module cml (/usr/share/texmf-tetex/tex/context/base/xtag-cml.tex ! Undefined control sequence. <argument> \c!variant =\v!a \xprocesscommaitem #1,#2->\if ,#1 ,\@EA \xprocesscommaitem \else \if ]#1\@EAE... \xdogetparameters #1]->\xprocesscommaitem #1,] ,\@relax@ l.23 \setupCMLappearance [ion] [\c!variant=\v!a] I assume this will go away once I switch to the most recent ConTeXt? Thanks, Joh