Sun Microsystems Inc. announced Baratz' resignation as President of Sun's Software Products and Platforms division Tuesday morning. Rumours of Baratz's departure began circulating on Monday. By Tuesday, Sun already was referring Baratz' calls to Warburg Pincus & Co., although he does not start work there until mid-August. Warburg senior managing director William Janeway said Baratz is in the process of "disentangling" himself at Sun and will be engaged in his new job within a couple of weeks. Although Janeway refused to say why Baratz chose to leave Sun, he said the opportunity to hire Baratz "came together very recently." Janeway has known Baratz since he was at IBM Corp. and takes credit for suggesting that Baratz join Sun when Sun formed its JavaSoft division in early 1996. In May, Baratz had been named to head Sun's software division, overseeing tools, developer relations and the Solaris and Java software groups, a promotion which took effect July 1. "This is a career shift for Alan, not a job change," Janeway said. "We are delighted at the great resources he brings to Warburg Pincus." Warburg Pincus is a private equity, global investor that manages $12bn (£7.3bn) in assets. The IT team takes a long view of investing, Janeway said, looking for discontinuities in markets and staying with a company for a minimum of five to seven years. Warburg first invested in Level One Communications in 1987, distributing the last of its stock last year. It has also invested in BEA Systems Inc., Veritas Software Corp. and Covad Communications. Baratz has both a master's degree and a doctorate in electrical engineering and computer science from the Massachusetts Institute of Technology and dealt with many startups while at Sun, Janeway said. Java licensees, meanwhile, praised Baratz as a passionate advocate for Java and expressed surprise at his departure. Ron Workman, senior vice president of marketing for Insignia Solutions Inc., said Baratz was instrumental in defining Sun's Community Source License Agreement, which allowed Insignia to protect its patents. "We hope Sun will continue in the same vein Alan laid out," Workman said. "Alan was very fair in treating us as a partner and not a competitor. He was very even-handed and responsive." IBM Corp., meanwhile, wished Baratz "good luck in his new endeavour." IBM's General Manager of Java Software Pat Sueltz said IBM "will continue to work with Sun and other industry leaders to ensure that Java evolves to meet the needs of our customers." Sun vice president and general manager of the Java platform, Jon Kannegaard will temporarily assume Baratz's role, reporting directly to Sun president Ed Zander.