Google map coding in default viewlisting templete

[Nealm]

I noticed in the viewlisting templete some coding at the top indicating that google map is already built into the templete. How do I get it to work.

The code I am seeing looks list this:
{* $Id: viewlisting.tpl.php,v 1.3 2006/04/19 17:48:46 Eric Exp $ *}
{* google maps*}
{$google_map_header}
{$google_map_js}
{* google maps*}
{* Display the breadcrumb *}
<p class="breadcrumb">
{if $friendly}
<a href="category/" class="breadcrumb">{$smarty.const.LANG_BROWSE_CATE GORIES}</a>
{else}
<a href="category.php" class="breadcrumb">{$smarty.const.LANG_BROWSE_CATE GORIES}</a>
{/if}
{foreach from=$breadcrumb item="entry"}
{$smarty.const.LANG_CAT_SEPERATOR} {$entry}
{/foreach}
</p>
{* Are you an administrator? *}
{if $smarty.session.userlevel==1}
{include file="viewlisting/listingadminlinks.tpl.php"}
{/if}
{* Now show the main table *}
<table class="tableborder">
<tr>
<th colspan="2"><strong>{$listingtitle}</strong></th>
</tr>
<tr>
<td valign="top" class="pformleft">
<table width="80%" border="0" cellpadding="0" cellspacing="3" class="norm">
<tr>
<td>{$google_map}</td> </tr>

So it appears that a google map feature is present, but how do I get it to work?