DOCBOOK-APPS: Why does xsltproc produce a segmentation fault when...

I have a problem with xsltproc...

I wrote a document like this:

<!DOCTYPE bibliography PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
  "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
<bibliography>
  <title>My title</title>
  <bibliodiv>
    ...
  </bibliodiv>
</bibliography>

When xsltproc processes this file, a segmentation fault occurs.
To fix the problem, I have to modify my document as following:

!DOCTYPE bibliography PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
  "/usr/share/sgml/docbook/xml-dtd/docbookx.dtd"
<bibliography>
  <title>My title</title>
  <bibliodiv>
    ...
  </bibliodiv>
</bibliography>

Yes, I have to replace the URL with a local URI.
Could somebody tell me why xsltproc behaves like this?

Is there a work around?

Thanks,

-- 
Giuseppe Greco
Fermo Posta
6928 Manno
Switzerland

Tel. : +41 76 390 60 32
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