PSGML problems

[Gleef <dzol virtual-yellow com>]

I've got two machines that I use, both are RedHat/i386 boxes with fairly
recent versions of things.  One is running Emacs 20.2 (from I think the
RH5.1 CD), the other Emacs 20.3 (from the RH5.2 CD).  Using the RPMs from
cygnus, I get PSGML working just fine on Emacs 20.2, but it won't work at
all on Emacs 20.3.

The psgml elisp programs load just fine, but whenever it tries to identify
and parse the DTD, it gives me a *SGML LOG* buffer with:
  External entity book not found
    Public identifier -//Davenport//DTD DocBook V3.0//EN
in it.  The sgml-catalog-files variable gets set properly ("CATALOG"
"/usr/lib/sgml/CATALOG"), but the only thing in sgml-catalog-assoc is
(("/usr/lib/sgml/CATALOG" (14040 39327))).  On the machine that works,
sgml-catalog-assoc gets filled with PUBLIC identifiers and their
corresponding information.

Has anyone else encountered this problem?  Is there a fix?  Do I have to
downgrade to Emacs 20.2 to get things working?

Thanks,
-Gleef