[tex-live] TL'09 pretest & XeTeX: "Cannot find Constantia.mf"

[Joel C. Salomon]

(Cross-post to XɘTeX & Τεχ Live lists; not sure where the problem lies.

This document works with XɘLatex under Tex Live 2008:

% !TEX TS-program = xelatex
% !TEX encoding = UTF-8
\documentclass{article}

\usepackage{fontspec, xunicode, xltxtra}
\setmainfont[Mapping=tex-text,Numbers={OldStyle,Proportional}]{Constantia}

\begin{document}
Some random text.
\end{document}

Under TL ’09, I get this error:

(c:/Users/chesky/Programs/TeXLive/2009/texmf-dist/tex/latex/base/fixltx2e.sty))
name = Constantia, rootname = Constantia, pointsize =
mktexmf: empty or non-existent rootfile!

kpathsea: Running mktexmf Constantia.mf
Cannot find Constantia.mf.

! Font \zf at basefont=Constantia at 10.0pt not loadable: Metric (TFM) file
or installed font not found.
\zf at fontspec ...ntname \zf at suffix " at \f at size pt
                                                  \unless \ifzf at icu
\zf at set@...
l.6 ...umbers={OldStyle,Proportional}]{Constantia}

?

—Joel Salomon