Microsoft is to extend a licensing program that forms part of its antitrust settlement with the US Department of Justice and some US states by two years. The surprise announcement came at a regular court hearing to assess the effectiveness of the settlement.

The Justice Department had expressed concern at the length of time it is taking to deal with problems in the terms of the licence offered by Microsoft.

Under the terms of the 2001 settlement, Microsoft is obliged to licence its software to manufacturers on uniform terms for five years, so that they can make their own software interoperable with the Windows operating system.

When it first made the code available, Microsoft did so on terms that rivals, including Sun Microsystems, deemed unreasonable. The Justice Department intervened and the licensing terms were eased. In January, when only eleven companies had signed up, the terms were made even more attractive.

Fourteen companies, including Sun and Time Warner, have now joined the program, but in an interim report to the Court last week, the Justice Department indicated that it was worried about the time spent "addressing numerous issues with Microsoft's implementation" of the licensing program. "This delay," said the report, "should not reduce the useful life of the licensed technology to current and potential licensees."

At a hearing yesterday, lawyers for Microsoft told US District Judge Colleen Kollar-Kotelly that the software giant would be willing to extend the program until November 2009, to take account of the time delays, according to CNET News.com.

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