[NTG-context] table-caption: centred or not??

Hello, how are the rules, that determine if the caption is centred? Here my test-case, "ok" means: this is how I like it and "not ok" means, I don't like it: \setupcaptions[width=\makeupwidth] \def\MyTable#1{\placetable{\dorecurse{#1}{bla }}{\starttable[|c|] \NC This is a table.\NC\AR\stoptable}} \starttext \MyTable{2} % ok \MyTable{10} % not ok \MyTable{30} % ok \setupcaptions[align=middle] \MyTable{2} % ok \MyTable{10} % ok \MyTable{30} % not ok \stoptext What should I do, to get 3 times "ok" ? Cheers, Peter -- http://pmrb.free.fr/contact/