div hidden issues with OSX Safari

[solokron]

I am using a div hidden table which works great with IE7, Firefox3, Opera9.5 and Safari (Win). When it comes to OSX Safari the browser completely ignores the hidden tag and loads the div. The div is set for onclick.

<script type="text/javascript">
function toggleBox(szdivID, iState) // 1 visible, 0 hidden
{
if(document.layers) //NN4+
{
document.layers[szdivID].visibility = iState? "show" : "hide";
}
else if(document.getElementById) //gecko(NN6) + IE 5+
{
var obj = document.getElementById(szdivID);
obj.style.visibility = iState? "visible" : "hidden";
}
else if(document.all)// IE 4
{
document.all[szdivID].style.visibility = iState? "visible" : "hidden";
}
}
</script>


<a href="#Jennifer" onclick="toggleBox('jenload',1);" value="Show div"><img src="images/adv3.gif" alt="Hear from Jennifer"/></a>


<div ID="jenload" class="Presentation"><div id="toload" style="position:absolute; top:200px; left: 50%; margin-left: -200px; z-index:999;"></div><script type="text/javascript" src="toload.js"></script></div>


How can this be changed to be OSX Safari friendly? I do not have a Mac so this is a bit frustrating for me.