[NTG-context] \definehighlight with style=command problem

I an trying to use \definehighlight to define a macro that will color and overstrike selected text. Thus far, \definehighlight[Delete][color=red,style={\overstrike}] \starttext test \Delete{test} test \stoptext reports ! Too many }'s. system > tex > error on line 4 in file ...TEST.tex: Too many }'s ... If I replace “\overstrike” with “bold”, “\Delete” works. “\overstrike” works otherwise, so am I trying the impossible here? Alan