[NTG-context] rotated cell bTABLE

Hi, the content (word "Umfang") of the the (nr=2) first row of this example should but turned +90°. Hmm ... just how to rotate the content of a cell? Thanks, Steffen === \starttext \bTABLE[align={middle,lohi}] \bTR \bTD[nr=2] {\bf Umfang} \eTD \bTD Absolut\eTD \bTD {\bf +} \eTD \bTD {\bf +} \eTD \bTD {\bf +} \eTD \bTD {\bf +} \eTD \bTD {\bf -} \eTD \bTD {\bf -} \eTD \eTR \bTR \bTD Relativ\eTD \bTD {\bf -} \eTD \bTD {\bf -} \eTD \bTD {\bf -} \eTD \bTD {\bf -} \eTD \bTD {\bf +} \eTD \bTD {\bf +} \eTD \eTR \eTABLE \stoptext