function changelang() {
	//document.write(location.href);
	var str = location.href;
	if (str.indexOf("L=1") > 0) {
		str = str.replace(/L=1/,"L=2");
	} else if (str.indexOf("L=2") > 0 ) {
		str = str.replace(/L=2/,"L=1");
	} else {
		// by default, visit the english version
		str = str + "&L=1";
	}
	window.location = str;
	return false;
}