Sun’s announcement includes Open ESB, an offering that is being released this week as an open source project called Glassfish (after the most transparent fish alive). And it is also open-sourcing the application server at the heart of its Java Enterprise System.

Tibco’s product, for now code-named Project Matrix, has early release scheduled during the first half of 2006.

Not surprisingly, initial releases are fairly modest in scope, designed to acquaint developers with the new infrastructures and – the vendors hope – jumpstart a new middleware product sector in much the same way J2EE created an appserver market. Sun’s initial offering will include software development kits for developing interfaces.

Meanwhile, Tibco’s initial releases will be a deployment platform for packaging services in a manner that complies with the specifications of JBI. The normalized router that is the center of the JBI-compliant enterprise bus will be implemented as a distributed extension of Tibco’s existing Rendezvous pubsub (publish and subscribe) integration backbone that has a strong foothold in the financial services and telco sectors.

In the future, Tibco will bulk up the normalized router with service containers for hosting services that will extend to non-Java components based on .NET, C++, or other code.

In related developments, Tibco is also announcing Project Ajax, which capitalizes on the General Interface rich browser client, which they acquired last fall. Ajax will be the visual development tool for churning out services.

While Tibco is not yet announcing pricing or final shipping dates, it is likely to price Ajax aggressively to maximize distribution.