[NTG-context] setup parameter problem

The code below seems ok in \startsection[title=] but not when I program the parameter collection with \def\setupparameters{\getparameters[prefix]} In that case even [title={enclosed value}] crashes with error message: Use of \doMacro doesn't match its definition. Obviously I am missing something here. What? \def\Macro{\dosingleargument\doMacro} \def\doMacro[#1]#2{#1X#2} The code below shows that it should be possible. \startsection[title=\Macro{arg} no braces needed]\stopsection \startsection[title={\Macro[arg1]{arg2} enclosed in braces}]\stopsection \stoptext dr. Hans van der Meer