Javascript display: None IE problem

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I've got this Javascript

function naviOff() {
	document.getElementById("clanSub").style.display = "none";
	document.getElementById("communitySub").style.display = "none";
	document.getElementById("downloadsSub").style.display = "none";
	document.getElementById("siSub").style.display = "none";
}

function naviClan() {
	document.getElementById("clanSub").style.display = "block";
	document.getElementById("communitySub").style.display = "none";
	document.getElementById("downloadsSub").style.display = "none";
	document.getElementById("siSub").style.display = "none";
}

function naviCommunity() {
	document.getElementById("clanSub").style.display = "none";
	document.getElementById("communitySub").style.display = "block";
	document.getElementById("downloadsSub").style.display = "none";
	document.getElementById("siSub").style.display = "none";
}

function naviDownloads() {
	document.getElementById("clanSub").style.display = "none";
	document.getElementById("communitySub").style.display = "none";
	document.getElementById("downloadsSub").style.display = "block";
	document.getElementById("siSub").style.display = "none";
}

function naviSI() {
	document.getElementById("clanSub").style.display = "none";
	document.getElementById("communitySub").style.display = "none";
	document.getElementById("downloadsSub").style.display = "none";
	document.getElementById("siSub").style.display = "block";
}

And on each navigational element, I have code like this

<li onmouseover="naviCommunity()"><a href="#">Community</a></li>

It works wonderfully in FireFox, but not in IE. Here's the page http://www.dishonor-elite.com