From the release page:
A Beta release of the Java 2 Platform, Standard Edition version
1.4 software for Windows, Linux, and Solaris is now available to
the Java community!Java 2 Platform, Standard Edition (J2SE) software is the premier
solution for rapidly developing and deploying mission-critical,
enterprise applications. Version 1.4 builds upon Java technology’s
cross-platform support and robust security model with new features
and functionality, enhanced performance and scalability, and
improved reliability and serviceability. Version 1.4 advances rich
client application development and provides the foundation for
standards-based, interoperable Web services that can be built and
deployed today!