Problem with \placefigure

["FrancoisFasoli" <fasoli@wanadoo.fr>]

The following test file gives a good result with old ConteXt
but gives an error with new ConteXt
It seems that new ConteXt does not accept [center]
What is the problem ?
Thanks

\starttext

\placefigure[center]{}{}

\stoptext

error message :

(c:/MesPGM/TeXLive/texmf-local/tex/ConteXt/base/spec-fdf.tex)
specials        : fdf loaded
)
specials        : fdf,tpd loaded
)
systems         : begin file test at line 1
floatblocks     : no block given
floatblocks     : 1 placed
! Undefined control sequence.
\OTRONEsomeherefloat ...\dorechecknextindentation

<argument> ...placesomeherefloat [\v!here ,center]
                                                  \else \dosavefloat \fi \fi
\secondoftwoarguments #1#2->#2

\dogetfloatbox ... \floatmethod \floatmethod }[#1]
                                                  \fi
\docompletefloat ...#5}{\preparednumber }}{#6}{#1}
                                                  \fi \fi \global 
\insideflo...
<argument> ...}{figure}{center}{figure}{}\nextbox
                                                  \else \docompletefloat 
{fi...
...
l.3 \placefigure[center]{}{}