startList = function() {

    if (document.all && document.getElementById) {
        
        navRoot = document.getElementById("nav");
        
        for (i = 0; i < navRoot.childNodes.length; i++) {
            node = navRoot.childNodes[i];
            
            if (node.nodeName == "LI") {
                node.onmouseover=function() {
                    this.className += " over";  
                }  
                
                node.onmouseout = function() {  
                    this.className = this.className.replace(" over", "");   
                }   
            }  
        } 
    }
}

window.onload = startList;