Apple says it is counting on the open-source heritage of its operating system to spare Mac OS X 10.4 (Tiger) from the security woes that have plagued Microsoft. Bertrand Serlet, senior vice president of software at Apple, said today that having a greater number of people working on the source code leads to better software security. “A lot of security problems derive from the core,” he told CNET “With open-source code, thousands of people look at the critical portions of source code and…check those portions are right. It’s a major advantage to have open-source code.”