signedMessage.setContent(mm);
signedMessage.saveChanges();
/* Create the encrypter */
SMIMEEnvelopedGenerator encrypter = new SMIMEEnvelopedGenerator();
encrypter.addKeyTransRecipient((X509Certificate)chain[0]);
/* Encrypt the message */
MimeBodyPart encryptedPart = encrypter.generate(signedMessage,
SMIMEEnvelopedGenerator.RC2_CBC, "BC");