Oracle said Wednesday that it’s buying Virtual Iron (VI), the Linux/Xen-based virtualization house that’s probably fourth in the queue after VMware, Microsoft and Citrix and maybe ahead of Red Hat and Novell.

The prospective purchase is a bit odd because Oracle already has its own Xen-based virtualization and is about to get a whole lot more of it when it takes over Sun, including Sun’s xVM Ops Center.

But apparently it wants VI’s management skills. And it wants to bedevil the virtualization leadership, or at least keep them out of its patch.

Oracle says it means to combine Virtual Iron’s widgetry with its own VM product expecting to get “more comprehensive and dynamic resource management across the full software stack” out of it.

That’s supposed to give users better capacity utilization, streamlined virtual server configuration and improved visibility and control of their enterprise software.

The odd bit there is that Virtual Iron’s been focused on SMBs; so does that mean Oracle’s going down-market? It wasn’t clear.

Oracle says it will produce a single integrated virtualization management solution for both physical and virtual environments.

It said the combination of Virtual Iron technology with its Enterprise Manager should make for more agility in meeting application service levels for virtual environments.

VI will also give Oracle the automation to reduce server power consumption and an open API.

Oracle didn’t say how much it’s paying for the joint but Virtual Iron raised $65 million in venture capital from folks like Intel, Goldman Sachs, Highland Capital and Matrix Partners.

The acquisition, an open secret for the last month or so, is supposed to close this summer. Oracle says it’s keeping VI staff and reviewing the existing VI product roadmap. It’s telling VI customers it’ll get back to them about directions.

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