By September 2007, all Belgian federal agencies must use software that can read reports, spreadsheets, presentations and other types of data files saved in OpenDocument (ODF), a free XML file format certified as a standard by the International Standards Organization (ISO) last month.

"If the impact analysis shows no adverse impact, ODF might even become the standard exchange format in September 2008," according to information posted on the Web site of the Belgian Government Interoperability Framework. Belgium joins the state of Massachusetts in a symbolic break from Microsoft. Massachusetts plans to make ODF its standard for all official government documents by Jan. 1.

Though it is a small country with just 10 million citizens, Belgium's embrace of ODF could have big ripple effects. Its capital, Brussels, is the headquarters of the European Union, making it an important political center in Europe.

The Danish and Norwegian governments are also considering moving to OpenDocument, according to Jason Faulkner, a member of the OpenDocument Fellowship, an ODF advocacy group.

"Given the current favorable attitude of the European Community to open standards, and, in particular, to the way that European governments and initiatives are defining open standards, it is not surprising that a growing number of European countries are moving to adopt ODF, which is conducive to not only proprietary but open-source implementations as well," said Andy Updegrove, an open-source advocate and Boston-based lawyer.