Sun Tuesday upgraded its open source x86 VirtualBox software - one of the items in its cupboard that IBM might have been interested in, presumably as a cloud hypervisor. It's a way to run Windows programs on Linux too.

The 2.2 rev supports the new Open Virtual Format 1.0 standard, which is supposed to make it way easier to move virtual machines - as well as virtual appliances now - from a development environment to a production environment on the desktop, the server or the cloud. Users can leave the old handwork that they have to do behind.

OVF will also make VirtualBox interoperable with other OVF widgetry.

VirtualBox 2.2 adds other significant performance enhancements.

The rev is described as the fastest release so far and there's 3D graphics acceleration for Linux and Solaris apps using OpenGL, which Sun claims will create a new class of programs to run in a VM.

It will support Snow Leopard, Apple's upcoming 64-bit platform, and it can handle guests with a fat 16GB of RAM.

There's a new host-interface networking mode that makes it easier to run server applications in VMs too.

Sun says VirtualBox has been downloaded 11 million times, a number that's quadrupled in the last year.

Free to individuals, commercial deployments start at $30 per user per year with 24/7 premium support. Sun is also cultivating OEM licensing.

For a download see www.sun.com/software/products/virtualbox/get.jsp. The 50MB software is supposed to install in five minutes.

Sun acquired VirtualBox from the German software house innotek around this time last year for stock.