BCCrypTool: A proof-of-concept utility for sending signed emails from a 
Java program.

Author:  Mark Heckler
Email:   mark.heckler@gmail.com
Twitter: @MkHeck

In order to compile and run this code, you'll need to obtain the following
libraries:
JavaMail (mail.jar)
JavaBeans Activation Framework (activation.jar) (not required in all cases)

And these Bouncy Castle crypto libraries from http://www.bouncycastle.org:

+ bcmail-jdk15on-147.jar
+ bcprov-jdk15on-147.jar
+ bcpkix-jdk15on-147.jar

DISCLAIMER: This code is provided as sample code, as-is, with no warranties 
either express or implied. Please feel free to take it and use it as you see
fit, but any results - good or bad - are entirely yours.  :-)