by , 8:25 AM EST, February 8th, 2007

Mac users looking to install Microsoft's new Windows Vista operating system need to check the fine print: The less expensive Home Basic and Home Premium versions are not authorized for use in virtual machine applications like Parallels Desktop. To stay complaint with Microsoft's licensing, you'll have to spring for the more expensive Vista Enterprise or Vista Ultimate, according to TECH.BLORGE.com.

The price difference between Vista Home Basic at US$199 and Enterprise at $299 has some calling this a "Mac tax," and that premium doesn't let you use all of the features in the Enterprise version. The licensing agreement points out that any content or applications that rely on Microsoft's DRM or BitLocker won't work, and then goes on to advise against using any products that offer alternative DRM protection schemes.

Despite the fact that Microsoft's strict licensing looks like it is designed to punish Mac users, it also impacts other Microsoft customers as well. Virtualization is not limited to the Mac and is very common on other platforms, including Windows. Windows users that rely on virtualization to run multiple versions of Microsoft's operating system at the same time for product testing or tech support are also bound by the same restrictive license.

Unlike Windows users, Mac users have a work around to avoid the $100 price hit thanks to Apple's Boot Camp. Where Parallels Desktop works as a virtual machine while your Mac is running Mac OS X, Boot Camp lets you choose at startup what operating system to boot. If you choose Windows, your Mac becomes a full-on PC, and is not emulating or running as a virtual machine.

For once, Mac and Windows users can claim they are being treated exactly the same. Unfortunately, it's under the dark cloud of Vista's licensing limitations.