Microsoft Corp. will disclose the source code of the Windows operating system to the Japanese government in line with the government's e-Japan project, company officials said Wednesday.

The move by the U.S. software giant marks a turnaround in Microsoft's policy on marketing its Windows software, whose closed-source code has so far been kept secret.

Commenting on Microsoft's announcement, an official of the Public Management, Home Affairs, Posts and Telecommunications Ministry said Tokyo's plan to conduct a study on open-source operating systems will not be affected.

Open-source programs do not require licensing fees and can be modified, since their code is freely available to anyone who wants to use it.

Problems with open-source software -- the best-known example being Linux -- are thought to be easier to fix than closed-source systems.

While Windows software is used on most of the government's servers and personal computers, the national and local governments have been considering switching to open-source operating systems.

Microsoft said it will push ahead in Japan with its so-called Shared Source Initiative, which is already under way overseas, providing open-source software to governments, universities and companies under individual contracts.

Microsoft said in a statement that it will actively participate in discussions on the e-Japan project, launched by Japan in a bid to become an information technology nation by 2005.

Toranosuke Katayama, minister of public management, home affairs, posts and telecommunications, told a House of Councilors committee last week that studies will be undertaken beginning fiscal 2003 with an eye to using open-source operating systems.