The JavaMail API provides a platform-independent and protocol-independent
framework to build mail and messaging applications. The JavaMail API is
implemented as a Java platform optional package and is also available as
part of the Java platform, Enterprise Edition. All Java EE application
servers, including GlassFish, provide an implementation of the JavaMail
API. The JavaMail implementation in GlassFish is the source code from wh
-ich the JavaMail reference implementation is built. Many other applica
-tion servers use the same JavaMail reference implementation.

WWW: http://java.sun.com/products/javamail/