[XeTeX] Discretionary hyphens don't work in paragraphed footnotes

[Peter Mukunda Pasedach]

Dear XeTeX list,

in the following example,

\documentclass[a4paper]{article}
\usepackage{fontspec}
\usepackage[para]{footmisc}
\begin{document}
\footnote{XXXXXXXXXXXXXX just a few normal words to fill up the line
  up to my word hy\-phe\-na\-te\-me}
\end{document}

the discretionary hyphens don't work. The combination required to
produce this behaviour seems to be xelatex + paragraphed footnotes
(here using the para option of footmisc, as it might be the easiest
example, but also with manyfoot, bigfoot and eledmac) + fontspec. It
looks like a bug to me. I've reported it here:
http://sourceforge.net/p/xetex/bugs/118/ , sorry if my mail now would
be considered crossposting, but I haven't seen any activity on this.

I should maybe mention that I'm dealing with critical editions of
Texts in Sanskrit in transliteration, for which, as far as I'm aware
of, there is no solution for a reasonable default hyphenation i.e. via
polyglossia, so that discretionary hyphens are the normal way of
taking care of proper hyphenation.

Peter