function email2friend(issue, article, isLoggedIn, isArticle) {
	//default values
	if (issue == null) {
		var issue = 0;
	}
	if (article == null) {
		var article = 0;
	}
	if (isLoggedIn == null) {
		var isLoggedIn = false;
	}
	if (isArticle == null) {
		var isArticle = no;
	}
	//send info to external tools
	if (isLoggedIn) {
		var url2go
		if (isArticle){
			url2go = "http://tools.atnext.com/email2friend/index.php?fuseaction=Engine.Form&site_id=apple&issue_id="+issue+"&art_id="+article+"&is_article="+isArticle+"&is_memberonly=yes&link="+escape(document.location.href);
		}else{
			var topic = article ;
			article = 0 ;
			url2go = "http://tools.atnext.com/email2friend/index.php?fuseaction=Engine.Form&site_id=health&issue_id="+issue+"&art_id="+article+"&is_article="+isArticle+"&is_memberonly=yes&topic="+topic+"&link="+escape(document.location.href);
		}
		
	//	var url2go = "http://10.111.50.130/email2friend/index.cfm?fuseaction=Engine.Form&site_id=health&issue_id="+issue+"&art_id="+article+"&is_article="+isArticle+"&is_memberonly=yes&link="+escape(document.location.href);
		window.open(url2go, "Email2Friend", "toolbar=no,scrollbars=no,width=520,height=600");
	} else {
		alert("對不起! 請先登入方可使用Email2friend功能。");
		//focus to login bar
		try{
			document.forms["loginForm"].elements["username"].focus();
		}catch(e){	}
	}
}