sfHover = function() {
	var sfEls = document.getElementById("nav").getElementsByTagName("LI");
	for (var i=0; i<sfEls.length; i++) {
		sfEls[i].onmouseover=function() {
			this.className+=" sfhover";
		}
		sfEls[i].onmouseout=function() {
			this.className=this.className.replace(new RegExp(" sfhover\\b"), "");
		}
	}
}
if (window.attachEvent) window.attachEvent("onload", sfHover);

   var currentItem = "link_1"; 
         function Navigation(Id) { 
             
            var CssClassActive = "current"; 
            var CssCLassInactive = "inactive"; 
             
            // Altem Item inaktive Klasse zuweisen 
            if(currentItem != "") { 
               document.getElementById(currentItem).className = CssCLassInactive; 
            } 
             
            // Neuem Item aktive Klasse zuweisen 
            document.getElementById(Id).className = CssClassActive; 
             
            // Neues Item merken 
            currentItem = Id; 
             
         }