How do I make my header into a Rollover image?

[HUMMERh3]

My main header is of a hummer and I wanted a user when he "mouses" over the image to show another image. http://www.hummerforum.org/hummers

I know how to make a roll over image in Dreamweaver...but where do I begin with Vb bulletin? Any help is appreciated!

The code for the logo in Style manager is the following:


<!-- logo -->
<a name="top"></a>
<table border="0" width="$stylevar[outertablewidth]" cellpadding="0" cellspacing="0" align="center">
<tr>
<td align="$stylevar[left]"><div align="center"><a href="$vboptions[forumhome].php$session[sessionurl_q]"><img src="$stylevar[titleimage]" border="0" alt="$vboptions[bbtitle]" /></a></div></td>
<td align="$stylevar[right]">&nbsp;

</td>
</tr>
</table>
<!-- /logo -->