"Recent Changes" page is not Valid XHTML becouse there is no "alt" attribute in <img> tags. Exaple from:
http://wiki.splitbrain.org/?do=recent
<li>2005-08-06 22:46
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<a href="/wiki:discussion:help" class="wikilink1" title="wiki:discussion:help" onclick="return svchk()" onkeypress="return svchk()">wiki:discussion:help</a>
<span class="user">61.68.83.13</span>
</li>