Because you're looking in the wrong spot.
From message_list.php:
<div class="postleft">
<dl>
<dt><strong><?php echo $username ?></strong></dt>
<dd class="usertitle"><strong><?php echo $user_title ?></strong></dd>
<dd class="postavatar"><?php if (isset($user_avatar)) echo $user_avatar ?></dd>
<?php if (isset($user_info)) if (count($user_info)) echo "\t\t\t\t\t".implode('</dd>'."\n\t\t\t\t\t", $user_info).'</dd>'."\n"; ?>
<?php if (isset($user_contacts)) if (count($user_contacts)) echo "\t\t\t\t\t".'<dd class="usercontacts">'.implode(' ', $user_contacts).'</dd>'."\n"; ?>
</dl>
</div>