VirtualBox, the German-made, cross-platform, x86 desktop virtualization software that Sun bought last year, graduates to the server with the 3.0 release that’s supposed to be announced today.

Sun says the widgetry can now create and run multiprocessor virtual machines that can handle heavyweight server-class workloads. It’s also getting enhanced graphics support for desktop-class workloads.

VirtualBox has previously been good only on one x86 CPU. It can now virtualize up to 32 virtual CPUs in a single virtual machine. To get to 32 figure starting with four quad-cores.

Sun recommends virtualizing only double the number of physical processors. One has to be careful that a system doesn’t gag because RAM gets scarce. RAM is the limitation.

Many multithreaded server workloads, such as database and web applications, can benefit from SMP systems that contain multiple CPUs.

Of course it remains to be seen what Oracle, which will be loaded with virtualization gear, will do with VirtualBox once its acquisition of Sun goes through this summer.

All Sun can say at this point is that it’s “better to have the IP than not to have the IP,” cold comfort for VirtualBox users.

There have reportedly been 14.5 million downloads of the stuff during its lifetime, eight million since last September, with four million registrations since October of 2007.

Sun says the API platform has been updated so it can be the basis of a community-driven Python-based VirtualBox Web Console project that will eventually let IT administrators manage their data centers from a web console.

Besides the server features in the new cut, VirtualBox 3.0 also supports Microsoft Direct3D for Windows guests. That means that graphically intense Windows programs such as computer modeling, 3D design and games can run in a virtual environment.

There’s also support for Open Graphics Library (OpenGL) 2.0. That’ll let high-performance Windows, Linux, Solaris and OpenSolaris graphical applications that typically use graphical hardware acceleration – stuff like Google Earth and CAM-based software – run on VirtualBox.

The new cut has also picked up support for a wider range of USB devices, including storage, iPods and phones.

VirtualBox remains free for individual use. Enterprise subscriptions, which include 24/7 support, start at $30 a head a year. Sun is also looking for OEMs

See www.sun.com/software/products/virtualbox/get.jsp.