IBM and Linden Lab, which operates Second Life, said Tuesday that have demonstrated virtual world interoperability by teleporting avatars between Second Life and an entirely different metaverse running on an OpenSim server.

The two companies are heralding the feat as a milestone, because it shows online virtual worlds could someday stop operating as closed environments and let avatars travel between metaverses. The development teams have posted a video documenting their accomplishment.

IBM and Linden lab hope that the protocol they developed for interoperability will eventually lead to an open standard that would enable users to cross virtual worlds as easily as people move from one Web site to another today.

"Interoperability is a key component of the 3D Internet and an important step to enabling individuals and organizations to take advantage of virtual worlds for commerce, collaboration, education, operations and other business applications," Colin Parris, VP of digital convergence at IBM, said in a statement.

The two partners plan to document the new technology on the Web site of the Architecture Working Group, an open forum that has developed a draft of a protocol to make Second Life accessible to other virtual worlds.

The extensions used to connect Second life to the OpenSim server will be made available to the open source community and the OpenSim community. OpenSim, built by the OpenSimulator Project, is an open source server designed for running 3D virtual worlds. Linden Lab is opening up a test area on its platform for organizations interested in developing the extensions further.

"IBM and Linden Lab both support an interoperable approach and see the industry moving to an interconnected model in the future," Ginsu Yoon, VP of business affairs for Linden Lab, said. "Interoperability is not only important for enterprise use but also has the potential to improve overall scalability and stability."

Interoperability has also become the battle cry among online social networks, such as MySpace and Facebook. Both have published application programming interfaces and development tools to allow third-party Web sites to offer services to members.