docbook-xsl spacing with manpage orderedlist

A project I'm working on is using docbook to produce manpages. However,
when we use orderedlists, the vertical spacing is confusing; there are
two blank lines between the preceding paragraph and the list, and no
blank lines between the list and the following paragraph.

For example, this XML:

-- >8 --
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
<refentry>
<refmeta>
	<refentrytitle>example</refentrytitle>
	<manvolnum>1</manvolnum>
</refmeta>
<refnamediv>
	<refname>example</refname>
	<refpurpose>example manpage</refpurpose>
</refnamediv>
<refsect1>
<title>DESCRIPTION</title>
<simpara>This is a paragraph, followed by a list:</simpara>
<orderedlist>
	<listitem><simpara>One</simpara></listitem>
	<listitem><simpara>Two</simpara></listitem>
	<listitem><simpara>Three</simpara></listitem>
</orderedlist>
<simpara>A new paragraph.</simpara>
</refsect1>
</refentry>
-- 8< --

produces this output:

-- 8< --
... [header omitted]
       This is a paragraph, followed by a list:


        1.  One

        2.  Two

        3.  Three
       A new paragraph.
... [footer omitted]
-- >8 --

I'm using docbook-xsl 1.73.2. Is this a bug, or are my expectations
somehow wrong?

-Peff