Sorry, coming in late here. The Env variable you need is LD_LIBRARY_PATH. Mine is set to
LD_LIBRARY_PATH=/usr/local/lib/:/usr/lib:/usr/local/ssl/lib:/usr/local/lib/m ysql Thanks, Tony and Michel. Unfortunately, LD_LIBRARY_PATH doesn't seem to solve it, which is really puzzling. The gory details are: My base Zope installation is /usr/local/zope/Zope-2.1.4-src. So, ExtensionClass.so is in /usr/local/zope/Zope-2.1.4-src/lib/python. My LD_LIBRARY_PATH is /usr/local/zope/Zope-2.1.4-src/lib/python:/usr/local/lib:/usr/openwin/lib, which ought to pick up ExtensionClass.so. Anything else which would cause the import to fail? I tried setting PYTHONPATH too, in desperation, but it doesn't seem to make any difference. Thanks, Zach Frey P.S.: I did try the binary distribution on Solaris 2.5.1, and can report that it doesn't work. Zope fails to start up with an unresolved symbol error, so it really does require 2.6+.