HELP - Navigation section missing in Mozilla 1.6

Hi there,

I designed the following page using Dreamweaver MX for windows.

http://www.ijc.customerdemo.com/index.asp

Everything works fine in IE6 and Netscape 6.1. However, I just downloaded the latest Mozilla 1.6 and the left navigation section "Our Services" is completely MISSING.

I am using CSS-2 and I have validated the HTML and CSS using the online W3C validator.

I would really appreciate some help in this as I have tried tweaking the CSS but to no avail.

The HTML section which is missing is:

<h1 class="leftcolumnheading"><img
src="/graphics/common/RightArrow-button1.gif" alt="Our services" width="15"
height="16" class="generalbuttoniconstyle3">Our Services</h1>
<div class="verticalnav2">
<ul>
..etc
</ul>
</div>
<div class="centeralign">
<img src="/graphics/common/BIMTA-logo.jpg" alt="British Independent Motor
Trade Association" width="70" height="97">
</div>

The CSS for this section is:

.verticalnav2 {
font-family: Verdana, Arial, Helvetica, sans-serif;
vertical-align: top;
text-align: right;
background-color: #FFFFFF;
height: 100%;
padding: 0px;
position: absolute;
visibility: visible;
}
.verticalnav2 ul {
padding: 0px;
list-style-type: none;
font-family: Verdana, Arial, Helvetica, sans-serif;
margin-bottom: 16px;
vertical-align: top;
list-style-image: none;
margin-right: 0px;
margin-left: 5px;
display: block;
}
.verticalnav2 ul li {
margin: 5px 10px 10px;
font-family: Verdana, Arial, Helvetica, sans-serif;
text-align: right;
white-space: nowrap;
}
.verticalnav2 ul li a:link {
text-decoration: none;
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size: x-small;
color: #406679;
text-align: right;
vertical-align: middle;
}
.verticalnav2 ul li a:visited {
text-decoration: none;
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size: x-small;
color: #406679;
text-align: right;
vertical-align: middle;
}
.verticalnav2 ul li a:hover {
margin: 0px;
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size: x-small;
color: #406679;
text-decoration: underline;
text-align: right;
vertical-align: middle;
}

Thanks in advance.

Vince