Your Ajax-Search is not XHTML-Valide...
It returns this code:
<form id="ajaxSearch_form" action="index.php?id=15" method="post">
<label for="ajaxSearch_input">
<input id="ajaxSearch_input" type="text" name="search" value="Suchtext eingeben..." onfocus="this.value=(this.value=='Suchtext eingeben...')? '' : this.value ;" />
</label>
<label for="ajaxSearch_submit">
<input id="ajaxSearch_submit" type="submit" name="sub" value="Suche!" />
</label>
</form>
<div id="ajaxSearch_output" style="opacity:0;filter:alpha(opacity=0);-moz-opacity:0.;" > </div>
And this code is valide:
<form id="ajaxSearch_form" action="index.php?id=15" method="post">
<fieldset>
<label for="ajaxSearch_input">
<input id="ajaxSearch_input" type="text" name="search" value="Suchtext eingeben..." onfocus="this.value=(this.value=='Suchtext eingeben...')? '' : this.value ;" />
</label>
<label for="ajaxSearch_submit">
<input id="ajaxSearch_submit" type="submit" name="sub" value="Suche!" />
</label>
</fieldset>
</form>
<div id="ajaxSearch_output" style="opacity:0;filter:alpha(opacity=0);-moz-opacity:0.;" > </div>
Pleace change it soon!

Or tell me how to change it myself .
-> I’ve only addet the HTML-Tag "<fieldset>"
The valide-version is looked from JOT ...
Or set a Parameter XHTML or somethink like this.