> Date: Tue, 10 Dec 2013 18:37:36 +0000
> From: Richard Copley <rcopley@gmail.com>
> Cc: Glenn Morris <rgm@gnu.org>, 16099@debbugs.gnu.org

>
> > Instead of working around the problem, just add a call to
> > unmsys--file-name there, like we do for other autoloads in that
> > Makefile.
> >
>
> A much better idea, thanks.
> I won't provide a patch, for copyright reasons. Sorry about that.

But does it work for you?