BALTIMORE (AP) _ Microsoft must include rival Sun Microsystems' Java programming language in its Windows operating system, a federal judge ruled Monday, handing Sun a victory as it pursues a private antitrust case against Microsoft.
Sun argued earlier this month before U.S. District Judge J. Frederick Motz that Microsoft has gained an unfair advantage by shipping Windows _ used by more than 90 percent of the world's personal computers _ with an outdated version of Java that's inconsistent for its users.
``In the final analysis, the public interest in this case rests in assuring that free enterprise be genuinely free, untainted by the effects of antitrust violations,'' Motz said in his ruling.
Java is designed to let programmers write software to run on all types of computers, whether they use Windows, Apple's Mac OS or some other operating system. Users may run into Java without knowing it when they visit Web sites that feature games or other applications.
Sun attorneys had argued that software developers are turning to Microsoft's .NET platform instead of gambling on Microsoft's spotty distribution of Java. Microsoft attorneys countered that at least half the world's software developers already use Java, which was designed to run small applications independent of any particular operating system.
In asking for the injunction, Sun said that if it waited until its $1 billion antitrust lawsuit against Microsoft was settled, it would be too far behind to compete.
Motz wrote that if Microsoft's system was to remain dominant, ``it should be because of .NET's superior qualities, not because Microsoft leveraged its PC monopoly to create market conditions in which it is unfairly advantaged.''
``Competition is not only about winning the prize; its deeper value lies in giving all those who choose to compete an opportunity to demonstrate their worth,'' he wrote.
Mike Morris, a Sun vice president, praised the ruling Monday afternoon.
``This decision is a huge victory for consumers who will have the best, latest Java technology on their PCs,'' Morris said, ``and it is a victory for software developers who will write applications to run on those PCs.''
Microsoft spokesman Jim Desler said the company plans to appeal.
``We're disappointed with today's ruling,'' Desler said, adding that it was ``premature'' to comment on when the latest version of Java will be included in the Windows system.
In the antitrust suit, Sun accuses Microsoft of intentionally creating incompatibilities with competitors' products. It also charges that Microsoft forced other companies to distribute or use products incompatible with Java.
The case is one of four private antitrust lawsuits that followed a federal judge's ruling in a lawsuit filed by the Justice Department and 18 states. The court found that Microsoft acted as an illegal monopoly based on its dominance in desktop operating systems.
In November, U.S. District Court Judge Colleen Kollar-Kotelly approved a settlement in that case barring Microsoft from retaliating against or threatening computer manufacturers. The settlement, which two states are appealing, also compels Microsoft to share key technical data with competitors that allow their programs to run more smoothly with Microsoft operating systems.