Sun Microsystems is scheduled to unveil two open source projects at the JavaOne developer conference in San Francisco later today.

The company plans to open the source code of its application server under the name Project Glassfish.

Sun will also try to create a new project to build an open source Enterprise Service Bus called Open-ESB. The project is being developed around the recently approved Java Business Integration specifications, also known as Java Specification Request 208.

An ESB forms a relatively new software category that promises to integrate and connect web services. The ESB market is made up mostly from start-up companies such as CapeClear and Sonic Software.

The European ObjectWeb open source consortium started development of an open source ESB called Celtix last year, and earlier this month BEA became the first major software vendor to launch a line of ESB products.

Both of Sun's projects will use the Common Development and Distribution Licence.

Although the licence is officially approved as open source, it faces criticism from supporters of the General Public Licence (GPL) for being too restrictive. The GPL is the most common open source licence.

The two projects kick off what Sun calls the "participation age", in which enterprise software users can steer the direction of software projects by participating in their development.

"This is to fuel the next age of computing," Joe Keller, Sun's vice president of marketing applications and developer platforms, told vnunet.com.

"It allows the communities to participate and have access in ways that they hadn't before, and deliver on the types of things that are needed to drive the age of participation."

However, Ron Schmelzer, a senior analyst with Zapthink, expressed reservations about the two projects, describing them as a "me too kind of thing ".

"These are all commodity products," he told vnunet.com. "That's what really bothers me about Sun. You can't see a million dollar ESB."

Schmelzer pointed out that Sun has been selling an application server for years, most recently as part of the Java Enterprise System bundles of enterprise application middleware.

The software has minimal share in a market dominated by IBM's WebSphere and BEA's products. There are also several open source application servers available from vendors including Red Hat and Jboss.

But Keller contended that Sun's application server is often used as a benchmark to test the performance of a newly developed Java application.

He expects the software to move from testing into production environments as a result of Sun's decision to open the source code.