[NTG-context] specify column-width, with option=stretch

[Peter Münster]

Hi,

I would like to specify the column-width of the first column to 5mm:

--8<---------------cut here---------------start------------->8---
\starttext
\setupTABLE[textwidth=99mm, option=stretch]
\setupTABLE[c][each][align={lohi, middle}]
\setupTABLE[c][1][height=5mm, style=\tfxx]
\framed[width=5mm, offset=0pt]{5}
\bTABLE
\bTR \bTD[nr=2] \setupinterlinespace[1.8ex] 1\\2\\3 \eTD
     \bTD bla \eTD \bTD blablabla \eTD \eTR
\bTR \bTD[nc=2] blabla \eTD \eTR
\eTABLE\par
\framed[width=99mm, offset=0pt]{99}
\stoptext
--8<---------------cut here---------------end--------------->8---

How could I do that please?

TIA for any hints,
-- 
           Peter