function createXHR() 
{
    var request = false;
        try {
            request = new ActiveXObject('Msxml2.XMLHTTP');
        }
        catch (err2) {
            try {
                request = new ActiveXObject('Microsoft.XMLHTTP');
            }
            catch (err3) {
		try {
			request = new XMLHttpRequest();
		}
		catch (err1) 
		{
			request = false;
		}
            }
        }
    return request;
}

function submitForm(id)
{ 
	var xhr = createXHR();
  
	var script = "envoi_mail.php";   // local script
	var msg='';
 	msg  = msg + 'Société : ' + document.ajax.societe.value + '<br>';
	msg  = msg + 'Civilité : ' + document.ajax.civilite.value + ' <br>';
	msg  = msg + 'Nom : ' +  document.ajax.nom.value + ' <br>';
	msg  = msg + 'email : ' + document.ajax.email.value + ' <br>';
	msg  = msg + 'tél : ' + document.ajax.tel.value + ' <br>';

	xhr.open("POST", script, true);		
	xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
	xhr.send("msg=" + msg + "&id=" + id); 

}