Hi, compiling the following file via lualatex --interaction=batchmode mbsp fails with an up-to-date TL2011: \listfiles \documentclass{article} \usepackage{fontspec} \begin{document} A \end{document} The command >tlmgr show l3kernel l3packages l3experimental shows for all packages > cat-version: SVN 2607 > cat-date: 2011-08-17 22:57:44 +0200 Best regards, Stephan Hennig From the log file: > ) (f:/texlive/2011/texmf-dist/tex/latex/tools/calc.sty > Package: calc 2007/08/22 v4.3 Infix arithmetic (KKT,FJ) > \calc@Acount=\count350 > \calc@Bcount=\count351 > \calc@Adimen=\dimen263 > \calc@Bdimen=\dimen264 > \calc@Askip=\skip262 > \calc@Bskip=\skip263 > LaTeX Info: Redefining \setlength on input line 76. > LaTeX Info: Redefining \addtolength on input line 77. > \calc@Ccount=\count352 > \calc@Cskip=\skip264 > )) (f:/texlive/2011/texmf-dist/tex/latex/l3packages/xparse/xparse.sty > ! Undefined control sequence. > <argument> \ExplFileName > > l.57 ...e}{\ExplFileVersion}{\ExplFileDescription} > > 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. > > ! Undefined control sequence. > <write> ...cls@pkg \space provides `\ExplFileName > '\@gobble \on@line . > l.57 ...e}{\ExplFileVersion}{\ExplFileDescription} > > The control sequence at the end of the top line