A US federal district court judge yesterday ordered Microsoft to turn over a key component of its Windows 95 and 98 operating systems to the US Justice Department.

Microsoft, currently the target of an antitrust lawsuit brought by the government, had objected to handing over its "source code" on grounds that it would pose a substantial risk to the integrity of its products.

The code is in effect the blueprint, or technological heart, of the operating systems.

At yesterday's hearing Judge Jackson also granted a Justice Department motion requiring Microsoft chairman Bill Gates to be available for a two-day deposition. Microsoft wanted the deposition limited to a single day.