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