[XeTeX] JPEG inclusion

[Jacques Ropers]

I guess I am making something wrong but I can't manage to include some 
jpegs using xelatex. The following code works with pdflatex whereas the 
jpeg does not appear in the pdf created by xelatex.

\documentclass[11pt, a4paper]{article}
\usepackage{graphicx}

\begin{document}
test\
\includegraphics[width=5cm,height=3cm]{logo}\\
test\\
\end{document}


Any help would be appreciated.
Thanks
Jacques.