Just to clarify matters: poi distributes the log4j jar file that it builds with. If you point your classpath to our log4j.jar file, poi will work.
If that is not possible (i.e., you're integrating poi into a system that already uses a conflicting log4j jar file), you need to replace our log4j.jar with a copy of yours and rebuild our code (the build.sh or build.bat files we provide should make that a trivial exercise).
