I think the same happened some time ago when the not-loading (horrible word, my english is rotting) of Latin Modern was still an experimental feature. Anyway, minimal example: %%%% start %%%% \usetypescript[libertine] \setupbodyfont[libertine,10pt] \starttext \startitemize[1] \item fail \stopitemize \stoptext %%% stop %%% It compiles just fine commenting the first 2 lines or with ConTeXt version 2011.01.26 09:01 While with the latest 2011.02.18 ! Math error: parameter \Umathquad\displaystyle is not set. system > tex > error on line 8 in file fail.tex: Math error: parameter \Umathquad\displaystyle is not set ... 1 \usetypescript[libertine] 2 \setupbodyfont[libertine,10pt] 3 4 \starttext 5 6 \startitemize[1] 7 8 >> \item fail 9 10 \stopitemize 11 12 \stoptext \mathematics ...rmalstartimath #1\normalstopimath \fi \dodosymbol ...bol \csname \??ss :#1:#2\endcsname \relax }\relax \donormalsymbol ...bol \redosymbol \currentsymbol \fi \fi \dodosymbol ...bol \csname \??ss :#1:#2\endcsname \relax }\relax \donormalsymbol ...bol \redosymbol \currentsymbol \fi \fi <to be read again> } ... l.8 \item f ail ? Sorry, but I can't typeset math unless various parameters have been set. This is normally done by loading special math fonts into the math family slots. Your font set is lacking at least the parameter mentioned earlier. Best wishes -- Marco