I'm not quite clear why LIBPATH is set. I set it (or LD_LIBRARY_PATH, depending on the OS), when I install Oracle or DBD::Oracle, but this is done manually just prior to installation. I do not set it in the profile, and it is not set for using Oracle on a day-to-day basis. I wonder if you are using some application that requires it. If you're not sure, why don't you unset it in your test system, and see if anything breaks