function prepNav(elementId) {
	if(!document.getElementById) return false;
	if(!document.getElementsByTagName) return false;
	if(!document.getElementById(elementId)) return false;
	
	var topNav = document.getElementById(elementId);
	
	var topNavLi = topNav.getElementsByTagName("LI");
	
	for (var i = 0; i < topNavLi.length; i++ )
	{
		topNavLi[i].onmouseover = function() {
			if (this.className)
			{
				this.className += " over";
			}
			else {
				this.className = "over";
			}
		}
		
		topNavLi[i].onmouseout = function() {
			if (this.className.search(/over/) != -1)
			{
				if(this.className == "over")
				{
					this.className = "";
				}
				else {
					this.className = this.className.replace(/over /, "");
					this.className = this.className.replace(/ over/, "");
				}
			}
		}
	}
					
}

function callPrepNav() {
	prepNav("top-nav");
}

addLoadEvent(callPrepNav);