SecExMail Secure Email 1.51
This e-mail encryption software uses RSA public key encryption and the Twofish block cipher.
It features PGP-style e-mail keys, but without the dependence on e-mail- software-specific plug-ins. Encryption keys are exchanged automatically.
The software runs unobtrusively as a relay agent in the system tray on your desktop and actively filters messages between your e-mail client and your mail server, encrypting and decrypting mail to and from known users in real-time.
The program is certified to operate with all SMTP POP3 e-mail clients, including Microsoft Outlook, Netscape Mail, IncrediMail, Pegasus, The BAT, Eudora and Calypso.
The program protects against cryptanalysis at the protocol level -- e-mail subject lines are encrypted. All attachments to secure messages are autoencrypted, including file names and MIME-type information. It is built on the Open SSL secure socket layer library.