Wednesday, October 9, 2002 07:00 AM
With PGP/GPG, it's the simplest, because it's modular. You can just work on the body text as a standalone document, sign/encrypt (ascii armor)/decrypt it separately, and just cut & paste, the entire signed/encrypted (ascii armored)/decrypted document, including the signature block, between the PGP/GPG application and the message body area of the mail client.
With S/MIME it is more complicated, because the headers and the return addresses of the message are involved, in determining the key and the encryption, signature etc. for the content.