function writeHTML(htmltxt, id) {
	document.getElementById(id).innerHTML = htmltxt;
}

function eraseHTML(id) { 
	document.getElementById(id).innerHTML = "";
}

function showTips(item)
{
	TipsContent = getCont('id', 'desc_'+item, null);
	setCont('id', 'tracer', null, TipsContent);
	document.getElementById('tracer').className = 'description';
}

function hideTips(item)
{
	TipsContent = getCont('id', 'desc_tracer', null);
	setCont('id', 'tracer', null, TipsContent);
	document.getElementById('tracer').className = 'tracertext';
}

function mOver(item) 
{
 document.getElementById('arrow_left_'+item).style.visibility = "visible";
 document.getElementById('arrow_right_'+item).style.visibility = "visible";
 showTips(item);
}

function mOut(item) 
{
 document.getElementById('arrow_left_'+item).style.visibility = "hidden";
 document.getElementById('arrow_right_'+item).style.visibility = "hidden";
 hideTips(item);
}

function submOver(item) 
{
 document.getElementById('arrow_left_'+item).style.visibility = "visible";
 showTips(item);
}

function submOut(item) 
{
 document.getElementById('arrow_left_'+item).style.visibility = "hidden";
 hideTips(item);
}

<!--
function MM_reloadPage(init) {  //reloads the window if Nav4 resized
  if (init==true) with (navigator) {if ((appName=="Netscape")&&(parseInt(appVersion)==4)) {
    document.MM_pgW=innerWidth; document.MM_pgH=innerHeight; onresize=MM_reloadPage; }}
  else if (innerWidth!=document.MM_pgW || innerHeight!=document.MM_pgH) location.reload();
}

MM_reloadPage(true);
//-->
<!--
 if(top!=self) {top.location=self.location; }
//-->


function httpRequest() {
	var xhr = false;
	if (window.XMLHttpRequest) {
		xhr = new XMLHttpRequest();
	} else if (window.ActiveXObject) { //Internet Explorer...
		try {
			xhr = new ActiveXObject("Msxml2.XMLHTTP");
			} catch (e) {
				try {
					xhr = new ActiveXObject("Microsoft.XMLHTTP");
					} catch (e) {xhr = null;}
			}
	}
	else { // XMLHttpRequest non supporté par le navigateur
    alert("Votre navigateur ne supporte pas les objets XMLHTTPRequest...");
	}
	return xhr;
}

function refreshBloc(id) {
	var xhr = httpRequest();
	if (!xhr) {
		alert('Abandon... Impossible de créer une instance XMLHTTP');
		return false;
	}
	writeHTML('Loading...', id);
	var url = "includes/"+id+".inc.php";
	xhr.open("GET", url, true);
	xhr.setRequestHeader("Content-Type", "text/html; charset=iso-8859-1");
	xhr.onreadystatechange = function() { 
			if (xhr.readyState == 4) {
				if (xhr.status == 200) {
					writeHTML(xhr.responseText, id);
				} else writeHTML('Random choice failed...', id);
			}
    };
	xhr.send(null);
}