Bowing to market realities, Microsoft said it will begin working with an ideological foe, open-source development and services company JBoss, on optimizing interoperability between JBoss' middleware and Microsoft's Windows Server software.

The deal doesn't mean Microsoft is softening its hard-line stance toward open-source development or becoming a Java enthusiast, Platform Technology Strategy Director Bill Hilf insisted. But with a significant number of JBoss customers deploying on Microsoft's platform, it's in both vendors' interests to ensure those deployments go smoothly, executives from the two companies said.

"Microsoft is not endorsing Java or J2EE [Java 2 Enterprise Edition] with this agreement. We will still compete heavily with .Net against Java," Hilf said. "But finding that shared customer base led us, like it should, to say, 'Customers are sure finding a lot of value in this. Can we do better?'"

This technical partnership is the first such alliance between Microsoft and Atlanta-based JBoss, which estimates that half its customers run its JBoss Enterprise Middleware System on Microsoft's Windows Server. (JBoss declined to disclose the overall size of its customer base.)

Precise goals for the newly formed alliance remain vague. Developers from the two companies will meet over the next year and, with input from joint customers, determine what new technologies and architectural guidance Microsoft and JBoss can offer to better align their software. Expected focus areas include integrated sign-on and identity management with Microsoft Active Directory, optimized SQL Server performance, and interoperability using the WS-* set of Web services standards.

One joint customer, First Consulting Group (FCG) Senior Vice President of Product Development Joseph Casper, hopes Microsoft and JBoss will optimize the ties between their software to increase scalability.

California-based FCG is a health care-focused software and services provider that has invested several million dollars building FirstGateways, a physician portal constructed atop JBoss middleware on Microsoft's platform. It selected JBoss and Microsoft to underpin its software because of cost and performance advantages: using open-source software made the project affordable, while Microsoft's platform offered the speed and stability FCG required, Casper said.

FCG's initial FirstGateways customer, the Swedish Medical Center in Seattle, went live on the software in early 2003 and now has 700 physicians using the portal. Another FCG customer in Cleveland uses it for 2,000 doctors. But FCG's goal is to expand FirstGateways nationally, to support the U.S. government's push to develop regional health information organizations (RHIOs).

"The system right now can scale to about 10 million unique users. That is not large enough to scale the nation," Casper said. "Our wish is that the combined Microsoft and JBoss work will optimize the performance of the JBoss engine on the Microsoft server. We created a hub-and-spoke architecture. If performance improves, we can expand how large a hub is, making these RHIO solutions much more valuable and cost-effective."

JBoss announced its Microsoft alliance just hours before the start of rival BEA Systems' BEAWorld conference in Santa Clara, California. Earlier this month, Oracle unveiled its dramatic Siebel Systems takeover deal the same morning that rival Salesforce.com Inc. kicked off its user conference, while Hewlett-Packard Co. announced plans to buy Peregrine Systems last week on the opening day of Oracle's OpenWorld show.