zope installation

[LeoDeBeo]

using redhat 7.1, i downloaded and installed the zope and zserver 
rpm-packages
i start zserver by typing: service zope start (sysV-initialization script)
it says that startup was ok but the server immediately dies
in the messages file (/var/log/messages), the following error pops up

zope: zserver.sh startup succeeded
z2[1381]: Startup exception: error: (91, 'Protocol wrong type for socket')

anyone an idea
help much appreciated