Docbook tags for formatting?

Peter,

I'd like to re-arrange the GUC parameter entries like this for readability (at
the request of several users who find the page hard to read).

=================================
listen_addresses (string)

Default: localhost
Set at: server start
Specifies the TCP/IP address(es) on which the server is to listen for
connections from client applications. The value takes the form of a
comma-separated list of host names and/or numeric IP addresses. The special
entry * corresponds to all available IP interfaces. If the list is empty, the
server does not listen on any IP interface at all, in which case only
Unix-domain sockets can be used to connect to it. The default value  allows
only local "loopback" connections to be made.
=================================

but I'm unsure what tags to use to set off the Default: and Set At: lines.
Suggestions?

I'm also noticing that only a relative handful of settings have "index terms".
Is there a reason for this?   It seems kind of random.

--
Josh Berkus
Aglio Database Solutions
San Francisco