<script type="text/javascript">
        $('#l-email').keypress(function (e) {
            if (e.which == 13) {
                $('form.login-form').submit();
                return false;    //<---- Add this line
            }
        });
        $('#l-password').keypress(function (e) {
            if (e.which == 13) {
                $('form.login-form').submit();
                return false;    //<---- Add this line
            }
        });
    </script>