* @param unknownTag Optional unknown tag number to test error handling
     * @return A byte array representing the ticket
     * @throws IOException on encoding error
     */
    private byte[] createTestTicketBytes(Number version, String realm, String principalName, int encType, byte[] encryptedData,
            Integer unknownTag) throws IOException {
        ASN1EncodableVector v = new ASN1EncodableVector();