Microsoft is expected to show a new friendliness to the open-source community by unveiling plans to release the source code to a part of its Silverlight technology at MIX 07 next week, according to sources familiar with the company’s plans.

Sources said Microsoft will also release a beta of Silverlight, a recently unveiled browser plug-in that allows Web content providers to offer a rich video and interactive media experience from directly within Web sites. The technology leverages Vista’s new graphics framework, Windows Presentation Foundation (WPF), and Microsoft is promoting it as a direct competitor to Adobe Systems’ Flash tool and delivery mechanism for rich multimedia content on the Web.