Quoting from the Microsoft official announcement:
Microsoft Corp. and Novell Inc. today announced the opening of the Microsoft and Novell Interoperability Lab in Cambridge, Mass. Announced last fall as part of Microsoft and Novell’s groundbreaking collaboration agreement, the opening of the lab delivers on a promise the two companies made to work together to create a joint development facility at which Microsoft and Novell technical experts will design and test new software solutions and work with customers and the community to build and support technologies that allow Microsoft® Windows Server and SUSE Linux Enterprise to work well together.
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Located in Cambridge, the 2,500-square-foot lab and workspace will be home to a combined team of the best and brightest Microsoft and Novell engineers focused on making Windows Server and SUSE Linux Enterprise work better together. The first priority for the lab team will be to ensure interoperability between Microsoft and Novell virtualization technologies. Additional work will include standards-based systems management, identity federation and compatibility of office document formats…
Microsoft already has an interoperability agreement with Novell in place since one year. It stacks with the new one Microsoft just signed with Sun, and with the implicit one with Citrix.