Sun Microsystems has filed a private lawsuit against Microsoft, accusing the company of harming competition by misusing its monopoly in the PC operating systems market to undermine Sun's Java technology.

The suit accuses Microsoft of hampering Java's success by distributing a version of the technology with its products that is not compatible with Sun's. Sun seeks a series of preliminary injunctions against Microsoft, one of which would require it to stop making Microsoft's JVM (Java virtual machine) download available and instead distribute a current version using Sun's technology with Windows XP and Internet Explorer.

Sun claims that Microsoft's "ultimate goal" is to dominate access to the Internet to the point where users would have to use a Microsoft product every time they connect to the Web. With its desktop and server operating systems, browser and .Net technology, Microsoft could create "choke points" for using the Internet, said Michael Morris, senior vice president and general counsel at Sun.

Java jammed In the new lawsuit, Sun charged that Microsoft tried to fragment the Java platform by "flooding the market" with Java Runtime Environments that are incompatible with Sun's technology. It accused Microsoft of forcing other companies to distribute or use incompatible products, and said the company is guilty of copyright infringement for distributing an unlicensed version of Java.

Sun was asked to confirm reports in which he was quoted as saying that the Sun suit seeks damages of more than US$1 billion. While Morris declined to give an exact figure, he said "substantial damages are provable" and that parts of Sun's hardware business had suffered due to Microsoft's actions.

The companies' legal battle over Java goes back to 1997, when Sun filed a lawsuit against Microsoft in which it made similar claims. As part of a settlement in that case reached in January last year, Microsoft agreed to pay Sun $20 million and adopted a new Java licensing agreement that greatly limited the way in which it could use Java. It was also barred from using the Java logo on its products.

Sun says the current lawsuit is broader in scope than that filed in 1997.

Real losers A Microsoft spokesman said the company has not had time to review the lawsuit, but had several immediate points to make.

"It's time to move past these issues, many of which are related to a lawsuit the parties settled last year," said Jim Desler, a Microsoft spokesman.

"Sadly, the real losers in this type of litigation are software developers. The industry is at its best when we focus on innovation and developing great products."

"This is Sun going to its last resort," said David Smith, senior analyst at Gartner. "They're not liking what the legal system has produced in terms of the antitrust case, and not having any other choice but to go after (Microsoft) in a private suit. I'm not the least bit surprised."