The Woodstock generation will be born again next year with the 20th anniversary of the landmark rock concert. The original promoters, John Roberts and Joel Roseman, are working with another promoter, Steve Gold, who attended the 1969 event, to market Woodstock memorabilia and to put together a reunion show. Gold, however, realizes they won't be able to re-create the same hippie mentality that made the 1969 show so distinctive. "We envision a worldwide event taking place over a three- or four-week period," he said. "We'll start off with a grass roots buildup in April. The 20th anniversary show will span a few continents. You're never going to re-create the actual Woodstock concert. It was spontaneous, it was magic and it can't happen again the same way. But we want to do something major and share it with the world." The only act named for the event now is Richie Havens, but Gold promises a major announcement "in the near future. Until then, we don't want to leak anything."