After holding off for a long time Red Hat has finally signed an OpenJDK Community agreement and joined the Open Java project.

The move will see all Red Hat engineers working on any and all of Sun Microsystems' free and open source projects.

Red Hat will also get access to Sun's Java test suite to ensure complete compatibility for developed Java applications.

Sacha Labourey, chief technical officer at JBoss, a division of Red Hat, said: "Through these strategic agreements, Red Hat commits to contribute to the Java platform and distribute a compatible, open source Java software implementation."

Less than five per cent of Java is now in a proprietary format and the OpenJDK Community aims to make the whole code completely open as soon as possible.

"This is excellent news. Over the past year or so we have learned a lot from some of Red Hat's best hackers: Andrew Haley, Mark Wielaard, Tom Fitzsimmons, Tom Tromey and Anthony Green," said Mark Reinhold, chief engineer for Java at Sun.

"They have been generous with their advice and patient with our progress toward truly open development."

The first collaboration is a project called IcedTea, a workaround in the next generation of Java that will get around proprietary binary plugs within Java to further open source the code.