ASN1InputStream stream = new ASN1InputStream(new ByteArrayInputStream(token));
        ASN1TaggedObject derToken;
        try {
            derToken = ASN1Util.as(ASN1TaggedObject.class, stream);
            if ( derToken.getTagClass() != BERTags.APPLICATION )
                throw new PACDecodingException("Malformed kerberos ticket");
            stream.close();
        }
        catch ( IOException e ) {