function SendMail(){
	var xhr=null;    
	if (window.XMLHttpRequest){        
	xhr = new XMLHttpRequest();    
	}    
	else if (window.ActiveXObject){        
	xhr = new ActiveXObject("Microsoft.XMLHTTP");	    
	}    
	//on définit l'appel de la fonction au retour serveur   
	xhr.onreadystatechange = function(){
		if(xhr.readyState < 4){
			document.getElementById('retour').innerHTML = '<img src="images/ajax-loader.gif" alt="traitement" />';
			}	
	if(xhr.readyState == 4 && xhr.status == 200){

			envoi_mail(xhr);					
		}		
	};
	if (document.forms[0].op[0].checked) {
	var type = "join_direct";
	}else{
	var type = "leave";
	}
	var email=document.forms[0].email_addr.value;
	var list=document.forms[0].list_id.value;
	var pop=document.forms[0].popup.value;
	xhr.open("POST", "newsletter/subscription_ajax.php", true);	
	xhr.setRequestHeader('Content-Type','application/x-www-form-urlencoded');	
	xhr.send("email_addr="+email+"&op="+type+"&list_id="+list+"&popup="+pop+"&hash=");
}
	
function envoi_mail(xhr){
	document.getElementById('retour').innerHTML = xhr.responseText;
}