Are longtime rivals Red Hat and Sun Microsystems making peace?

If not a full-fledged peace treaty, they have at least reached a ceasefire.

Red Hat (NYSE: ) disclosed plans Monday to join the Java programming language open source movement in agreement with Sun Microsystems, one of its biggest global rivals. Financial terms weren’t disclosed other than Red Hat, the world’s top Linux open source software developer, said that “all Red Hat engineers” would be involved in “all” Sun-led open source projects.

Red Hat and Sun, developer of Unix-based products, have been rivals for years as Red Hat and other Linux firms battled to win market share from Unix. The news help send Red Hat shares up 38 cents to close at $21.88 on Monday.

As part of the agreement, Red Hat also signed a license agreement with Sun for the Java Platform Standard Edition as part of Sun’s Open JDK (Java Development Kit).

While Red Hat produces one-eighth the quarterly revenue of Sun on an annual basis ($400 million vs. the $3.2 billion Sun announced on Monday), the Raleigh-based company is a world leader in the open source and Linux communities.

Red Hat will share knowledge generated by its developers with Sun as part of the agreement.

ChannelWeb reported that the announcement had apparently been in the works for several months.

“Red Hat’s OpenJDK embrace formalizes a strategy shift forecast earlier this year at JavaOne, where Red Hat engineer and veteran open-source developer Tom Tromey said he would argue internally for shifting Red Hat’s Java development resources away from splinter projects and toward OpenJDK, the official, open-source core of the Java SE specification released this year,” ChannelWeb reported.

"My view has always been that one good implementation is better than competing bad implementations," Tromey said, according to ChannelWeb.

Matt Asay, a blogger about open source at, hailed the announcement.

“Hopefully this agreement will spur others beyond Red Hat to collaborate on Java development,” Asay wrote. “Java and .Net (from Microsoft) continue to be major forces within the enterprise. The more collaboration to drive open-source Java forward, the better for companies worried about lock-in.

\“Now here’s one wild, probably ridiculous thought: What would happen if this initial agreement paved the way for these two companies to collaborate on a wide range of projects? Would a merger make sense at some point? Stranger things have happened.”

Red Hat made the Java announcement at virtually the same time it said company executives will hold a press conference on Wednesday at noon to discuss the company’s “vision.”

According to Red Hat, it is the “first major software vendor” to license the Java SE Technology. Sun announced plans in 2006 to make Java open source.

Red Hat said it will also pursue development of Java tools for inclusion in its biggest seller – Red Hat Enterprise Linux.

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

“IcedTea,” a project combining Fedora and projects at Red Hat, should benefit quickly from the Java agreement, Red Hat added.

"Sun welcomes Red Hat to the OpenJDK community," said Rich Green, executive vice president, software at Sun, in a statement. "It is a vote of confidence to have Red Hat, a leader in open source, engaging with the community on such a broad scale. When we open-sourced our Java software implementation, we hoped to see just this kind of collaboration between the GNU [general public license]/Linux world and the Java technology ecosystem. It is gratifying to see the promise of open-source Java technology coming true with Red Hat’s leadership."