// pvno [0] INTEGER 5
        v.add(new DERTaggedObject(true, 0, new ASN1Integer(Integer.parseInt(KerberosConstants.KERBEROS_VERSION))));
        // msg-type [1] INTEGER 14 (AP-REQ)
        v.add(new DERTaggedObject(true, 1, new ASN1Integer(Integer.parseInt(KerberosConstants.KERBEROS_AP_REQ))));
        // ap-options [2] BIT STRING

        principalVector.add(new DERTaggedObject(true, 0, new ASN1Integer(1))); // name-type
        principalVector.add(new DERTaggedObject(true, 1, new DERSequence(principalNameVector)));
        v.add(new DERTaggedObject(true, 2, new DERSequence(principalVector)));

        ASN1EncodableVector encPart = new ASN1EncodableVector();
        encPart.add(new DERTaggedObject(true, 0, new ASN1Integer(encType)));

            ev.add(new DERTaggedObject(true, 0, new DERSequence(fields)));
            final ByteArrayOutputStream collector = new ByteArrayOutputStream();
            final ASN1OutputStream der = ASN1OutputStream.create(collector, ASN1Encoding.DER);
            final DERTaggedObject derApplicationSpecific = new DERTaggedObject(false, BERTags.APPLICATION, 0, new DERSequence(ev));
            der.writeObject(derApplicationSpecific);