Example element isn't kept together

[Erik Leunissen <e.leunissen@hccnet.nl>]

The attached docbook xml and xsl stylesheet exercise the keeping 
together of a docbook example element (as advertised in documentation).

In this case, the example is not succesfully kept together when 
converting to PDF using xsltproc and fop1.1

So what's wrong?

Thanks in advance for any help,

Erik Leunissen.

<?xml version="1.0" encoding="UTF-8"?>
<section version="5.0" xmlns="http://docbook.org/ns/docbook";
         xmlns:xlink="http://www.w3.org/1999/xlink";
         xmlns:xi="http://www.w3.org/2001/XInclude";
         xmlns:svg="http://www.w3.org/2000/svg";
         xmlns:m="http://www.w3.org/1998/Math/MathML";
         xmlns:html="http://www.w3.org/1999/xhtml";
         xmlns:db="http://docbook.org/ns/docbook";>
  <title>Example handling</title>

  <para role="spacer">This paragraph is used to push the example below across
  a page boundary. To that end this paragraph has a role "spacer", and a
  space-after.optimum attribute on such paragraphs is used in the
  corresponding xsl stylesheet.</para>

  <example>
    <title>Mastering level: recognition (not to be expected in real
    exam!)</title>

    <para role="mc_stem">Which of the following is an atmospheric
    compartment:</para>

    <orderedlist numeration="loweralpha" role="mc_itemlist">
      <listitem>
        <para>space</para>
      </listitem>

      <listitem>
        <para>oxygen</para>
      </listitem>

      <listitem>
        <para>the troposphere</para>
      </listitem>

      <listitem>
        <para>odour</para>
      </listitem>
    </orderedlist>
  </example>
</section>

Attachment: example.xsl
Description: application/xslt