well.. As much as the theme is nice,The Author's page itself does not validate..
You have actually two duplicated search forms, one in the sidebar and one in the tabbed thingie.
one is this :
<div id="content_5" class="content">
<form id="searchBox" method="get" action="http://petpundit.com">
<div>
<input id="s" name="s" type="text" value="" size="44" tabindex="8" />
<input id="searchsubmit" name="searchsubmit" type="submit" value="Find" tabindex="9" />
</div>
</form>
</div>
and the other one here :
<li id="search">
<h3><label for="s">Search</label></h3>
<form id="searchform" method="get" action="http://petpundit.com">
<div>
<input id="s" name="s" type="text" value="" size="10" tabindex="10" />
<input id="searchsubmit" name="searchsubmit" type="submit" value="Find" tabindex="11" />
</div>
</form>
</li>
That creates duplicates.
So either Try to remove the sidebar one (second) , or change the ID to Class in css.