Here is yet more evidence that the virtualization market is maturing as VMware competitors advance their technology: The open source Xen virtualization project will soon support Windows.

On Monday, XenSource, the company that manages the development of the Xen hypervisor and sells subscription and support services for it, is expected to announce that the open source virtualization technology now can run Windows virtual machines.

Previously, Xen supported only Linux and NetBSD. XenSource is adding Windows support to the XenEnterprise product it debuted in August and is targeting it at the Windows midmarket, hoping to provide them with an easy to use, less-expensive alternative to VMware.

Windows support in XenEnterprise is expected to be available in a beta program beginning Nov. 6 and is expected to be generally available for Windows 2003 and Windows XP in December. XenSource plans to add Windows 2000 support in the first quarter of next year, XenSource executive say.

XenEnterprise for Windows includes a number of features including Xen and guest-operating-system installers, tools to migrate physical systems into virtual machines and a wide range of management capabilities.

It will be priced starting at about $488 for an annual subscription license for a two-processor server, the company says.

“This is a fully packaged and supported virtualization platform that includes the Xen hypervisor and offers high performance for both Windows and Linux guests,” says John Bara, vice president of marketing at XenSource. “Automated installation and a management console is included . . . . The average Windows IT professional can get this up and running in 10 minutes.”

XenSource executives concede that XenEnterprise doesn’t have all the bells and whistles of VMware, which introduced its broad VMware Infrastructure 3 package in June. Pricing for VMware Infrastructure 3 starts at around $1,000 for two processors.

“There is a big gap in the market between VMware at the high end and some of the free stuff like [Microsoft] Virtual Server at the low end,” Bara says. “We’re looking to occupy that space with XenEnterprise and provide what we call volume virtualization – virtualization for the rest of us.”

Xen is tapping into the hardware-based virtualization capabilities embedded into new chips from Intel and AMD to provide the Windows support, says Simon Crosby, CTO at XenSource.