<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;">Dear Nicola,<br><br>Thanks for the links to learn metapost. I will definetly try out them. <br><br>Even though I commented out the <span style="font-family: monospace;">lines </span>\usepackage{dvidrv}
\usepackage{hrefout}, I have got the same errors as before. I am able
to compile the file in my other computer which uses texlive 2007
version. I think the problem is about the metapost of tevlive 2009
version. <br><br>After I get some experience for metapost, I may tackle with the problem myself. <br><br>Regards,<br>Ozhan <br></td></tr></table><br>