Windows Vista is illegal in EU law, according to an industry body. The ECIS (European Committee for Interoperable Systems) claims Microsoft has not fulfilled its obligations outlined in the company's 2004 agreement with the European Commission.

The ECIS is an international non-profit that strives to promote consumer choice. Members include many who aren't exactly best mates with Microsoft: Nokia, Adobe, Corel, IBM, Opera, Oracle, RealNetworks, Red Hat, and Sun Microsystems.

The ECIS claims Microsoft is yet to make an "interoperability disclosure" guaranteeing an even playing field for other software houses. The body made a fresh complaint in 2006 and has appealed to the European Commission antitrust body to put the brakes on the US giant.

According to the Committee, "this will stifle competition on the PC and server markets, and extend its closed standards into the open standards based internet environment."

Simon Awde, ECIS Chairman said that, "with Vista, Microsoft has clearly chosen to ignore the fundamental principles of the Commission's March 2004 decision."

"Vista is the first step in Microsoft's strategy to extend its market dominance to the Internet. Vista and Microsoft Office 2007 will also introduce the Open XML file format (OOXML), by which Microsoft seeks to displace ODF, the existing ISO approved, truly open document file format."

We're awaiting comment from Microsoft and will bring it to you when we get it.