[pstricks] Problem with psscalebox and !

[Martin Chicoine]

\psscalebox fails with babel and the ! parameter of psgraph as in the
following example :

\documentclass{article}

\usepackage[francais]{babel}
\usepackage{pstricks-add}

\begin{document}				

\psscalebox{.5}{%
  \begin{psgraph}(0,0)(-2,-2)(2,2){.5\textwidth}{!}
    \psplot[algebraic]{-2}{2}{sin(x)}
  \end{psgraph}
}

\end{document}