[NTG-context] Multiline formula numbering problems

Hi, I cannot understand why, but multiline formulas are not numbered. \starttext % has number \placeformula \startformula f(x_0, u_0)=0. \stopformula % has no number \placeformula \startformula \startalign \NC \dot{x}(t) \NC=f(x(t), u(t)) \NR \NC y(t) \NC=h(x(t), u(t)), \NR \stopalign \stopformula % no numbers even here \startsubformulas \placeformula \startformula \dot{x}(t)=f(x(t), u(t)) \stopformula \placeformula \startformula y(t) =h(x(t), u(t)), \stopformula \stopsubformulas \stoptext Regards, Vyatcheslav