<div>Hi </div>
<div>During the trimming down process, I found the culprit which appears to be the "iftex" package.</div>
<div> </div>
<div>%******************************************************<br>\makeatletter\let\ifGm@compatii\relax\makeatother<br>\documentclass{beamer}</div>
<div>
<p>\usepackage{iftex} % Compiles with xelatex only if commented</p>
<p>\usepackage{fontspec}<br>\setromanfont[Mapping=tex-text]{Futura Std Medium}</p>
<p>\begin{document}<br>\begin{frame}<br>lorem ipsum<br>\end{frame}</p>
<p>\end{document}</p>
<p>%******************************************************<br></p>
<p>Best regards,</p>
<p>Jacques </p><br><br> </div>
<div><span class="gmail_quote">On 6/1/10, <b class="gmail_sendername">Will Robertson</b> <<a href="mailto:wspr81@gmail.com">wspr81@gmail.com</a>> wrote:</span>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">Hi Jacques,<br><br>Thank you very much for the feedback.<span class="q"><br><br>On 2010-06-01 20:24:21 +0930, Jacques ROPERS <<a onclick="return top.js.OpenExtLink(window,event,this)" href="mailto:jropers@gmail.com" target="_blank">jropers@gmail.com</a>> said:<br>
<br><br>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">However on the same document, xelatex now hangs with the following error<br>message:<br><br>! Undefined control sequence.<br>
<argument> ..._mode_tl {node}\luatexprehyphenchar<br> =`\-\luatexposthyphenchar<br>...<br>l.68 ...nt = {Futura Std Bold}]{Futura Std Medium}<br></blockquote><br></span>This doesn't make much sense to me; I can't imagine how this happens. Would you be able to trim down your document into a minimal example of the problem and post it here? Also, which version of LuaTeX are you using?<br>
<br>Best regards,<br><span class="sg">Will<br><br><br><br><br></span></blockquote></div><br>