function Ajax()
	{
	var xmlhttp=false;
	// POUR FIREFOX
	if (!xmlhttp && typeof XMLHttpRequest!='undefined')
		{
    try
		{xmlhttp = new XMLHttpRequest();}
		catch (e) {xmlhttp=false;}
    }
	//AUTRE
	if (!xmlhttp && window.top.createRequest)
    {
    try
		{xmlhttp = top.createRequest();}
		catch (e) {xmlhttp=false;}
    }
	//IE
	if (!xmlhttp && window.top.ActiveXObject)
		{
		try {xmlhttp = new top.ActiveXObject("Msxml2.XMLHTTP");}
		catch (e)
			{
			try {xmlhttp = new top.ActiveXObject("Microsoft.XMLHTTP");}
			catch (E)	{xmlhttp = false;}
    	}
    }
	return xmlhttp;
	}