document.getElementsByClassName = function(cl) {
    var retnode = [];
    var myclass = new RegExp('\\b'+cl+'\\b');
    var elem = this.getElementsByTagName('*');
    for (var i = 0; i < elem.length; i++) {
        var classes = elem[i].className;
        if (myclass.test(classes)) retnode.push(elem[i]);
    }
    return retnode;
}


var CNid
if(navigator.appName == "Microsoft Internet Explorer")
	{
		CNid = 2;
		}
else if(navigator.appName == "Netscape")
	{
		CNid = 3;
		}

var nav_link = document.getElementsByClassName("nav_link");
for(var i=0; i<nav_link.length; i++){
	nav_link[i].onmouseover=function(){
		this.className="nav_over";
		if(this.childNodes[CNid]){
			this.childNodes[CNid].style.display="block";
		}
		}
	nav_link[i].onmouseout=function(){	
		this.className="nav_link";
		if(this.childNodes[CNid]){
			this.childNodes[CNid].style.display="none";
			}		
		}
		
	}
	
var nav_link2 = document.getElementsByClassName("nav_link2");
for(var i=0; i<nav_link2.length; i++){
	nav_link2[i].onmouseover=function(){
		this.className="nav_over2";
		if(this.childNodes[CNid]){
			this.childNodes[CNid].style.display="block";
		}
		}
	nav_link2[i].onmouseout=function(){	
		this.className="nav_link2";
		if(this.childNodes[CNid]){
			this.childNodes[CNid].style.display="none";
			}		
		}
		
	}