AttributeError: 'module' object has no attribute 'flock'
If you try installing Plone on an IBM Thinkpad or PC, its Python install conflicts with the Plone one.
On new IBM factory PCs, you will often find an installation of an "IBM Tools" suite. This suite is installed with its own version of Python (python22 in our case). As a result, Python22 is referenced in the System Path.
The solution to this particular problem is to remove all references to the previous Python installation (including Path, PYTHONCASEOK, PYTHONPATH Environment variables, %SystemRoot%\system32 pythonXX.dll's). Only when all references are removed (and you uninstall/reinstall) will the Plone installation be successful.
Note: Simply removing references and attempting to run an already installed instance of Plone will fail.
For reference, we are attaching the error string received when we would run runzope.bat before the problem was fixed:
C:\Program Files\Plone 2\Data\bin>runzope C:\Program Files\Plone 2\Data\bin>"C:\Program Files\Plone 2\Python\python.exe" "<br> C:\Program Files\Plone 2\Zope\lib\python\Zope\Startup\run.py" -C "C:\Program Files\Plone 2\Data\etc\zope.conf"<br> C:\Program Files\Plone 2\Python\lib\fcntl.py:7: DeprecationWarning: the FCNTL module is deprecated; please use fcntl DeprecationWarning) Traceback (most recent call last): File "C:\Program Files\Plone 2\Zope\lib\python\Zope\Startup\run.py",line 49, in run() File "C:\Program Files\Plone 2\Zope\lib\python\Zope\Startup\run.py", line 19,in run start_zope(opts.configroot)<br>File "C:\Program Files\Plone 2\Zope\lib\python\Zope\Startup\__init__.py", line 49, in start_zope<br>starter.makeLockFile() File "C:\Program Files\Plone 2\Zope\lib\python\Zope\Startup\__init__.py", line 251, in makeLockFile<br>lock_file(self.lockfile) File "C:\Program Files\Plone 2\Zope\lib\python\Zope\Startup\misc\lock_file.py", line 40, in lock_file<br>fcntl.flock(file, fcntl.LOCK_EX | fcntl.LOCK_NB) AttributeError: 'module' object has no attribute 'flock'

Also...
See also:
http://mail.zope.org/[…]/005130.html
esp. comment 5. I don't recall if only fixing PYTHONCASEOK works.