The very frustrating thing is that I installed many things from tarballs, build from sources, etc... I also have flawlessly working copies on my OS/X and WInd XP, just the darn AIX is giving me a headache. I believe I missed someting in the configuration which points to my (existing] zlib, or the object code is "unloadable". Mat, thanks for your effort. I will abandon this - the support on AIX seems to be awfully sparce. Lanny -- Posted via http://www.ruby-forum.com/.