function changeLang( lang )
{
   //set the language cookie
   SetCookie('language', lang);
  
   var url = window.location.href;
   var newUrl = url;
   
   htmIndex = url.indexOf(".htm");
   
   if(htmIndex == -1){
   	//not an html page;
   	refresh();
   }
   else{
   	
   	if(lang == "en"){
   	   var fIndex = url.indexOf("_f.");
   	   if(fIndex != -1){
   	   	newUrl = url.substring(0, fIndex) + url.substring(htmIndex);
   	   }
   	}
   	else if(lang == "fr"){
   		var eIndex = url.indexOf("_e.");
   		if(eIndex != -1){
		   newUrl = url.substring(0, eIndex) +"_f"+ url.substring(htmIndex);
   	   	}
   	   	else{
   		   newUrl = url.substring(0, htmIndex)+"_f"+url.substring(htmIndex);
   		}
   	}
   	
   }
   
   //change location
   window.location.href = newUrl;
}

function onerror(msg, URL, lineNum){
	if(msg.indexOf("NS_ERROR_FILE_NOT_FOUND" != -1)){
		//go to home page
		var defUrl = window.location.protocol+
					window.location.hostname+"/";
		window.location.href= defUrl;
		return true;
	}
}

<!-- Original:  Ronnie T. Moore -->
<!-- Web Site:  The JavaScript Source -->

<!-- This script and many more are available free online at -->
<!-- The JavaScript Source!! http://javascript.internet.com -->

<!-- Begin
var expDays = 30;
var exp = new Date(); 
exp.setTime(exp.getTime() + (expDays*24*60*60*1000));

function getCookieVal (offset) {  
	var endstr = document.cookie.indexOf (";", offset);  
	if (endstr == -1)    
		endstr = document.cookie.length;  
	return unescape(document.cookie.substring(offset, endstr));
}


function GetCookie (name) {  
	var arg = name + "=";  
	var alen = arg.length;  
	var clen = document.cookie.length;  
	var i = 0;  
	while (i < clen) {    
		var j = i + alen;    
		if (document.cookie.substring(i, j) == arg)      
			return getCookieVal (j);    
		i = document.cookie.indexOf(" ", i) + 1;    
		if (i == 0) break;   
	}  
	return null;
}


function SetCookie (name, value) {  
	var argv = SetCookie.arguments;  
	var argc = SetCookie.arguments.length;  
	var expires = (argc > 2) ? argv[2] : exp;  
	var path = (argc > 3) ? argv[3] : "/";  
	var domain = (argc > 4) ? argv[4] : null;  
	var secure = (argc > 5) ? argv[5] : false;  
	document.cookie = name + "=" + escape (value) + 
	((expires == null) ? "" : ("; expires=" + expires.toGMTString())) + 
	((path == null) ? "" : ("; path=" + path)) +  
	((domain == null) ? "" : ("; domain=" + domain)) +    
	((secure == true) ? "; secure" : "");
}


function DeleteCookie (name) {  
	var exp = new Date();  
	exp.setTime (exp.getTime() - 1);  
	var cval = GetCookie (name);  
	document.cookie = name + "=" + cval + "; expires=" + exp.toGMTString();
}

function langselect () {
	var favorite = GetCookie('language');
	if (favorite != null) {
		switch (favorite) {
		case 'en' : 	url = 'index_e.htm'; 
	     	break;
		case 'fr' : 	url = 'index_f.htm'; 
	     	break;
		}
		window.location.href = url;
	}
}


/* ---- Constants -- */
var selectedStyleClass = "selected";

/* ---- Functions -- */
function markAsSelected(id){
	var link = document.getElementById(id);
	link.setAttribute("class", selectedStyleClass);
	link.setAttribute("className", selectedStyleClass);
}

function preloadImg(url){
   img = new Image();
   img.src = url;
}

function MM_findObj(n, d) { //v4.01
  var p,i,x;  if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
    d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
  if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
  for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
  if(!x && d.getElementById) x=d.getElementById(n); return x;
}

function MM_swapImage() { //v3.0
  var i,j=0,x,a=MM_swapImage.arguments; document.MM_sr=new Array; for(i=0;i<(a.length-2);i+=3)
   if ((x=MM_findObj(a[i]))!=null){document.MM_sr[j++]=x; if(!x.oSrc) x.oSrc=x.src; x.src=a[i+2];}
}

function MM_swapImgRestore() { //v3.0
  var i,x,a=document.MM_sr; for(i=0;a&&i<a.length&&(x=a[i])&&x.oSrc;i++) x.src=x.oSrc;
}

function enableElement(formElement, flag)
{
	formElement.disabled = flag;
}

function refresh()
{
    //  This version of the refresh function will be invoked
    //  for browsers that support JavaScript version 1.2
    window.location.reload( true );
}