To all the above fanboy posts: FF ISN'T BETTER, it renders just as poorly, but has additional js problems and has quirkier CSS.
The moral of this story is to validate your source and not rely on a single browsers failure to display pages correctly as according to the specifications in which the site is written for the page to be displayed.
The code is atrocious, and I'd just rewrite it all in valid xhtml, ditching the js messyness for a simple css imageswap, but for now please just take the revbar out of the div and add the ">" to the end of its script element and it'll display better.
BEFORE:
<div id="html1" style="position:absolute; overflow:hidden; left:0px; top:1px; width:61px; height:38px; z-index:0">
<script LANGUAGE="javascript" SRC="http://www.revora.net/bar.js"></SCRIPT</div>
SHOULD BE:
<script type="text/javascript" src="http://www.revora.net/bar.js"></script>