<..context supp-mps..>
\long\def\:temp{\begingroup \obeyMPlines \dostartMPcode}
\ifx \startMPcode\:temp
\pend:def \startMPcode{%
\let\:temp\begingroup
\def\begingroup{\let\begingroup\:temp
\a:MPcode
\begingroup
\aftergroup\b:MPcode }%
}
\fi
\NewConfigure{MPcode}{2}
-_-_-