Red Hat will release a Java application server at the LinuxWorld conference next week, expanding beyond the operating system market for the first time.

Red Hat Application Server will be sold on a subscription basis with services and support, in a similar pricing model to that which Red Hat uses for its Linux OS. Pricing will be announced on Monday.

The software is based on JOnAS (Java Open Application Server), an open source application server developed by ObjectWeb, a nonprofit middleware consortium in Europe. It incorporates the Apache Software Foundation's Tomcat Java servlet engine and Struts, a software framework for building Java Web applications, the sources said.

Red Hat said last August that it would work with ObjectWeb to offer a Red Hat-branded application server. A beta version was released in December. Representatives for Red Hat and ObjectWeb declined to comment on their plans.

Red Hat Application Server will compete with proprietary offerings from the likes of BEA, IBM and Oracle. It will also turn up the heat on JBoss, the leading open-source Java server vendor.

One effect of the open source products has been to apply pricing pressure to the proprietary vendors, analysts have said. Sun, which has struggled to boost its middleware business, offers a low-end version of its application server for free.

Red Hat said last year that it would also release clustering software to link groups of servers together and programming tools based on the open source Eclipse project. Along with the application server, the products comprise what it calls its Open Source Architecture, a collection of server software for businesses that runs on its Linux OS.

ObjectWeb was founded in 2002 to foster the development of a range of open source middleware. Along with Red Hat, its members include Bull, France Télécom and the French National Institute for Research in Computer Science and Control.