Microsoft and Sun Microsystems squared off against each other in court yesterday as the rival software giants began giving evidence in their bitter contract dispute over Java. The two-day evidentiary hearing is a warm-up before tomorrow's hearing on Sun's motion seeking a preliminary injunction to force Microsoft to stop shipping Windows 98 and the recently released Java development tool Visual J++ 6.0 Bob Muglia, senior vice president in charge of applications and tools, was Microsoft's central witness. Later today, Sun executive and Java co-creator, James Gosling is scheduled to give testimony. He will be joined by Alan Baratz, president of the Java software division and Sun's in-house lawyer Lee Patch, who are also scheduled to take the stand. The majority of Muglia's time on the stand was spent walking US District Court Judge Ronald Whyte through the series of meetings in 1996 that ultimately led to the early morning signing of the final Java contract on March 12 of that year following a marathon 20 hour negotiation between representatives from Sun and Microsoft. The deal came more than a year after Microsoft had already begun development of its own version of Java and the virtual machine. But during his cross-examination, Sun attorney Lloyd (Rusty) Day got Muglia to admit that the contract did not specifically empower Microsoft to change the Java language or create dialects of Java. Microsoft's addition of new keywords and compiler directives to Java are critical to Sun's claims that Microsoft violated its license agreement. Muglia also agreed with Day's statement that the communications between the parties leading up to the contract's signature were irrelevant. "The deal is the deal" said Muglia. During his testimony, Muglia contended that Microsoft won the right to extend both the Java language, the so-called Java Virtual Machine, and compilers to help developers create Windows-specific applications. Muglia, who did not deny that Microsoft had extended Java, said it was contractually free to incorporate the additions. Muglia also referred to an e-mail sent by Microsoft executive Roger Heinen to Sun co-founder Bill Joy that that is still under seal by the court. Muglia left the inference that Microsoft had flexibility in its use of Java with regards to Windows. The e-mail was sent on Dec 6, 1995 - one day before Microsoft signed a letter of intent to license Java. Microsoft called two of its expert witnesses. MIT economics professor Jerry Hausman claimed software developers should be free to choose between "plain or Microsoft Java," adding that such a choice improved the economy by creating competition. "Windows is not an essential facility," Hausman said. "Netscape has delivered 12 million copies of its browser in 3 months. They don't need Microsoft's distribution channels for that." Hausman said that if Microsoft were forced to distribute Sun's Java Virtual Machine, it would result in "free-riding," where one company is forced to do another company's economic bidding. "If Budweiser is forced to distribute Miller beer, Budweiser won't invest as much and Miller won't compete as hard. On cross-examination, Hausman also refused to concede that Microsoft forced technical lock-in by forcing Java developers to use Windows native interfaces. "I don't agree that Microsoft Java programs couldn't run on other VMs. It could force developers to better integrate their programs and create better applications. Professor Peter Lee of Carnegie Mellon said Microsoft's Visual J++ 6.0 was easier for developers to use because it not force them to write special glue to integrate Java with native code, unlike Sun's tools. Lee also discussed the differences between Sun's and Microsoft's native interfaces for Java applications.