var http = false;

if(navigator.appName == "Microsoft Internet Explorer") {
	http = new ActiveXObject("Microsoft.XMLHTTP");
} else {
	http = new XMLHttpRequest();
}

// var activeId = 'm1';
var activeId = '';
function menu(name, id) {
	http.open("GET", name, true);
	http.onreadystatechange = function() {
		if ( http.readyState == 4 ) {
			document.getElementById('mainText').innerHTML = http.responseText;
		}
	}
	http.send(null);
	if ( id != activeId ) {
		var el = document.getElementById(id);
		el.className = 'visit';
		if ( activeId != '' ) {
			el = document.getElementById(activeId);
			el.className = '';
		}
		activeId = id;
	}
}