mfpic and context pdf support files

[Guy Worthington <guyw@multiline.com.au>]

This one's too low level for me -- I've no idea where to start
debugging it:

The latest ConTeXt Beta (2002.5.26) won't work with the 
mfpic package (0.5.0).

I've attached a minimal example, and the resultant log:

%--------------------------------------------------
\input mfpic
\usemetapost

\bye
%--------------------------------------------------

This is pdfeTeX, Version 3.14159-1.00b-pretest-20020211-2.1 
(Web2c 7.3.7) (format=pdfetex 2002.5.14)  3 JUN 2002 11:37
entering extended mode
**tryMFpic.tex
(./tryMFpic.tex{c:/Local/TeX/texmf-var/pdftex/config/pdftex.cfg}
(c:/Local/TeX/texmf-local/tex/generic/mfpic/mfpic.tex
MFpic: 2001/10/30 version 0.5.0 beta. 
\mfp@out=\write0
\mfp@graph=\read1
\mfp@count=\count27
\mfp@linetype=\count28
\mfp@toks=\toks13
\every@tlabel=\toks14
\@fdc=\count29
\@wholegraph=\box16
\@textbox=\box17
\mfp@scratch=\dimen16
\mfp@n=\count30
\mfp@sequence=\count31
\mfpicheight=\dimen17
\mfpicwidth=\dimen18
\mfpframesep=\dimen19
\mfpframethickness=\dimen20
\mfp@verbtex=\toks15
) (c:/Local/TeX/texmf-local/tex/context/base/supp-pdf.tex
(c:/Local/TeX/texmf-local/tex/context/base/supp-mis.tex
loading : Context Support Macros / Missing
\protectiondepth=\count32
\scratchcounter=\count33
\scratchtoks=\toks16
\scratchdimen=\dimen21
\scratchskip=\skip18
\scratchmuskip=\muskip10
\scratchbox=\box18
\scratchread=\read2
\scratchwrite=\write1
\zeropoint=\dimen22
\nextbox=\box19
\nextdepth=\dimen23
\everyline=\toks17
\!!counta=\count34
\!!countb=\count35
\recursecounter=\count36
)
loading : Context Support Macros / PDF
\nofMPsegments=\count37
\nofMParguments=\count38
Runaway argument?
\par 
! Forbidden control sequence found while scanning use of \beginETEX.
<inserted text> 
                \par 
<to be read again> 
                   \newdimen 
l.1284   \newdimen
                  \MPcriteriumA \MPcriteriumA=512pt
? s
OK, entering \scrollmode...
\MPcriteriumA=\dimen24
\MPcriteriumB=\dimen25
! Undefined control sequence.
l.1287 \endETEX

The control sequence at the end of the top line
of your error message was never \def'ed. If you have
misspelled it (e.g., `\hobx'), type `I' and the correct
spelling (e.g., `I\hbox'). Otherwise just continue,
and I'll forget about whatever was undefined.

\everyMPtoPDFconversion=\toks18
) )
No pages of output.