[NTG-context] table background color in first row

Hi there, I have s simple table like this: \starttext \starttable[|l|l|] \NC \bf Colheader 1 \NC \bf Colheader 2 \NC \SR \HL \NC cell 11 \NC cell 12 \NC \FR \NC cell 11 \NC cell 12 \NC \LR \stoptable \stoptext and like to have a light gray background for the heading row. I found documentation about \setupTABLE which on the one hand I did not fully understand how to use and on the other hand I'm not quite sure how far this is the way it is done nowadays. -- Thanks, Manfred