Silicon Valley’s best-known venture firm, Kleiner Perkins Caufield & Byers, has teamed up with Sevin Rosen Funds to invest $6 million in XenSource, of Palo Alto.

XenSource offers a so-called open source virtualization technology, which we’ll leave for open source fans to comment on. But as XenSource’s folks put it, virtualization “allows enterprises to realize significant savings from server consolidation running multiple operating systems and mission critical applications on a single server.”

Kleiner’s Kevin Compton and Sevin Rosen’s Nick Sturiale will join the board. Founders include the leader of the Xen project, Ian Pratt of the University of Cambridge, Nick Gault, an enterprise software veteran and formerly founder of Network Physics, and Open Source veteran and openMosix leader Moshe Bar. Pratt and his co-founders at the University of Cambridge will continue to
develop the technology and manage the Xen Open Source community project, the company said.

More at www.xensource.com