Jens I am sorry to say that I have compiled all software on this machine. I have done so so that I would not have confusion due to different compilers. I think that there is a problem with the manner in which I compile Python or compile usingPython. Python has a zlib.so in its distribution but somehow it is not getting through to the compilation of Zope. There must be something about compiling Python or compiling using Python that I do not understand. I think it has something to do with the zlib module. Either the zlib module should be made a part of Python at the time I compile Python or the compiler should be told to use the zlib module at the time I compile Zope. The zlib module is included in the Zope 2.6 distribution which is the reason that I have no trouble installing and using 2.6.