From the 'They Told Us So' files:

Back in February, Microsoft and Red Hat announced a somewhat unlikely deal to validate each others virtualization interoperability.

Now eight months later,the two 'partners' have announced that the testing and validation is now complete.

That means that Microsoft Hyper-V is now validated by Microsoft and Red Hat to run Red Hat Enterprise Linux 5.2, 5.3 and 5.4 guests. On the other side, Red Hat Enterprise Linux 5.4, using the Kernel Virtual Machine (KVM) hypervisor, with Windows Server 2003, 2008 and Windows Server 2008 R2 guest is now validated.

I don't know what that means for RHEL 5.3 users, the press release doesn't spell it out (and as of the time of this blog post I wasn't able to get in contact with Red Hat).

NO this isn't the same kind of deal that Novell has with Microsoft. This is just a simple straightforward interoperability deal born out of necessity in my view. Simply put, Red Hat is the Linux leader and Microsoft (like it or not) needs to work with them on areas that are of mutual benefit.

It's a sentiment that Microsoft has echoed in their public statement on this (now validated) interoperability deal.

"This work is a step forward for customers, partners and hosting providers who want to offer their customers the main x86 virtualized operating systems to run applications," said Mike Neil, general manager of Windows Server and Server Virtualization at Microsoft Corp in a statement. "Customers now get improved virtualization support between the two companies so they can confidently deploy new applications and services."

Does this completed interoperability testing in any way imply that Microsoft doesn't see open source and Red Hat in particular as infringing on patents? That's still the big question that is hanging in the air in my opinion.

Frankly, I can't see Microsoft suing Red Hat users for patent infringement when Microsoft itself is now telling customers that the two technologies can interoperate (albeit virtually).