The two software makers already have a close relationship, going back to 1989. As a result of a new agreement, they will announce that Microsoft is validating version 5 of the XenServer hypervisor, Citrix's virtualisation software, for use with the Windows Server 2008 operating system.
The news emerged at a roundtable hosted by Citrix, but the agreement will come as little surprise to industry watchers. Microsoft showed signs of wanting to extend its presence in the virtualisation market recently when it relaxed the licensing that limited the use of its own Hyper-V hypervisor. Then, earlier this week, it said that it was giving Hyper-V away for free.