protected void Login1_Authenticate(object sender, AuthenticateEventArgs e)
        {
            string username = Login1.UserName;
            string pwd = Login1.Password;

            ServiceReference.ServiceAgendaClient servAgenda = new ServiceReference.ServiceAgendaClient();
            bool ret = servAgenda.CheckUser(Login1.UserName, Login1.Password);

            if (ret)
            {
                connecte = true;
                Session["UserAuthentication"] = username;
                Session.Timeout = 1;
                Response.Redirect("connexion.aspx");
            }
        }