[XeTeX] \emph{} exceeds TeX capacity with slides

[Pablo Rodríguez]

Hi there,

for some strange reason using both XeTeX and LuaTeX the \emph{} command 
contained in the sample document below exceeds TeX capacity:

\documentclass[12pt]{slides}
\usepackage{fontspec}
\setsansfont{FreeSans}
\begin{document}
hi \emph{hello}
\end{document}

This only happens when fontspec is loaded with the slides as documentclass.

I guess this might be a bug in fontspec (I use TL2010 and I updated all 
new packages today).

Could anyone confirm this?

Thanks for your help,


Pablo.