This SMIME Messenger can generate and read S/MIME messages.
There are some limitation for use because of this implementation,
but it can operate "Signing", "Encryption", and "Signing + Encryption"
with email messages, and "Decryption" and "Signing verification"
is available for S/MIME messages.

Limitation is following :
 * only "RC2 40bit" symmentric cipher is used for encryption and
    decryption.
 * AiCrypto S/MIME can not operate any MultiPart analysis. Therefore,
    the Clear Signature message type is not available to use.
 * Signature and message will be embeded in smime.p7s file.
 * Verification process requires the certificates, which should be
    embeded in the S/MIME message.