function portfolio_links() {
  	var sfEls = document.getElementById("links").getElementsByTagName("LI");
  	for (var i=0; i<sfEls.length; i++) {
  		sfEls[i].onmouseover=function() { this.className+="hover"; }
  		sfEls[i].onmouseout=function() { this.className=this.className.replace(new RegExp("hover\\b"), ""); }
  	}
}

addLoadEvent(portfolio_links);