Hi, I've been trying to use the \overrightarrow command within a metapost graphic, but it doesn't work. Math mode does work, for example \vec works like expected. Outside of metapost, \overrightarrow works as expected. To illustrate the problem, I've created the following simple testcase: \starttext \startMPcode draw btex $\vec{foo}$ etex; draw btex $\overrightarrow{foo}$ etex; \stopMPcode \stoptext This gives the following error output: ! Undefined control sequence. \dodosmash [#1]->\edef \@@smash {#1}\futurelet \nexttoken \dododosmash \relbar ->\mathrel {\smash -} \mtharrowfill ...inmuskip \thickmuskip \relax #8#5 \mkern -#1mu \cleaders \hb... \dodohandlemathoverarrow ...{\ialign {##\crcr #2#3 \crcr \noalign {\kern #1\n... \mathpalette ...>\mathchoice {#1\displaystyle {#2} }{#1\textstyle {#2}}{#1\sc... <argument> ...ex; draw btex $\overrightarrow {foo} $ etex; ... l.5 \stopMPcode It seems the \overrightarrow command uses \@@smash, which isn't defined when running from metapost? Is this expected? Is this a bug? Gr. Matthijs