return SOAResource{}, &nestedError{"MBox", err}
	}
	serial, off, err := unpackUint32(msg, off)
	if err != nil {
		return SOAResource{}, &nestedError{"Serial", err}
	}
	refresh, off, err := unpackUint32(msg, off)
	if err != nil {
		return SOAResource{}, &nestedError{"Refresh", err}
	}
	retry, off, err := unpackUint32(msg, off)
	if err != nil {
		return SOAResource{}, &nestedError{"Retry", err}
	}