Cell-Highlight in IE , Firefox , Opera , usw.

PHP-Code:
<tr>
<td class="{$bgcolor}" align="center" valign="top"><img src="{$theme['imgdir']}/{$lightbulb['folder']}.gif"forumicons/{$lightbulb['folder']}" alt="{$lightbulb['altonoff']}" title="{$lightbulb['altonoff']}" /></td>
<td class="{$bgcolor}" alt="trow1" valign="top">
<strong><a href="forumdisplay.php?fid={$forum['fid']}">{$forum['name']}</a></strong><div class="smalltext">{$forum['description']}{$modlist}{$subforums}</div>
</td>
<td class="{$bgcolor}" valign="top" align="center" style="white-space: nowrap">{$threads}{$unapproved['unapproved_threads']}</td>
<td class="{$bgcolor}" valign="top" align="center" style="white-space: nowrap">{$posts}{$unapproved['unapproved_posts']}</td>
<td class="{$bgcolor}" alt="trow1" valign="top" align="right"left" style="white-space: nowrap">{$lastpost}</td>
</tr>

<SCRIPT LANGUAGE="JavaScript"> 
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var statusMessage = 'Willkommen im Börsenportalforum'; 
window.status = statusMessage; 

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for(ch=0;ch<cellHigh.length;ch++) { 
if ((cellHigh[ch].className=="trow1" && cellHigh[ch].valign=="top" )  || (cellHigh[ch].className=="trow1" && cellHigh[ch].alt=="trow1") || (cellHigh[ch].className=="trow2" && cellHigh[ch].valign=="top" )  || (cellHigh[ch].className=="trow2" && cellHigh[ch].alt=="trow1")) { 
if (cellHigh[ch].width=="100%") {var num=0;} else {var num=1;} 
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</script>