$ mkdir pytest
$ cd pytest
$ mkdir src
$ mkdir stage
$ mkdir src/mylib
$ touch src/mylib/__init__.py
$ echo 'import mylib' > src/myscript.py
$ cd src
$ zip mypar.zip mylib/__init__.py myscript.py
  adding: mylib/__init__.py (stored 0%)
  adding: myscript.py (stored 0%)
$ mv mypar.zip ..
$ cd ..
$ mv mypar.zip stage
$ cd stage
$ mkdir mylib
$ env PYTHONPATH=$PWD/mypar.zip python -m myscript
Traceback (most recent call last):
  File "/var/tmp/Python-1-fb-buildroot/usr/local/lib/python2.6/runpy.py", line 121, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "/var/tmp/Python-1-fb-buildroot/usr/local/lib/python2.6/runpy.py", line 34, in _run_code
    exec code in run_globals
  File "/home/dreiss/pytest/stage/mypar.zip/myscript.py", line 1, in <module>
TypeError: expected string or Unicode object, NoneType found
$ env PYTHONPATH=$PWD/mypar.zip python ../src/myscript.py
$