public boolean revokeCert(BigInteger serialNumber, CRLReason reason) throws Exception {
ProtectedPKIMessageBuilder builder = new ProtectedPKIMessageBuilder(
PKIHeader.CMP_2000, requestorSubject, responderSubject);
builder.setMessageTime(new Date());
builder.setTransactionID(randomTransactionId());
builder.setSenderNonce(randomSenderNonce());
CertTemplateBuilder certTempBuilder = new CertTemplateBuilder();
certTempBuilder.setIssuer(caSubject);
certTempBuilder.setSerialNumber(new ASN1Integer(serialNumber));
AuthorityKeyIdentifier aki = new AuthorityKeyIdentifier(caSubjectKeyIdentifier);
byte[] encodedAki = aki.getEncoded();
Extension extAki = new Extension(Extension.authorityKeyIdentifier, false, encodedAki);
Extensions certTempExts = new Extensions(extAki);
certTempBuilder.setExtensions(certTempExts);
ASN1Enumerated asn1Reason = new ASN1Enumerated(reason.getValue().intValue());
Extensions exts = new Extensions(
new Extension(Extension.reasonCode, true, new DEROctetString(asn1Reason.getEncoded())));
RevDetails revDetails = new RevDetails(certTempBuilder.build(), exts);
RevReqContent content = new RevReqContent(revDetails);
builder.setBody(new PKIBody(PKIBody.TYPE_REVOCATION_REQ, content));
ProtectedPKIMessage request = build(builder);
PKIMessage response = transmit(request, null);
return parseRevocationResult(response, serialNumber);
}