[gutsy] Fails with (nautilus:7546): Nautilus-Python-WARNING **: could not import gobject

Nautilus extensions in Python fail to work. Launching Nautilus from the console gives the following error message:

(nautilus:7546): Nautilus-Python-WARNING **: g_module_open libpython failed: libpython2.5.so: cannot open shared object file: No such file or directory
Traceback (most recent call last):
  File "/var/lib/python-support/python2.5/gtk-2.0/gobject/__init__.py", line 30, in <module>
    from gobject.constants import *
  File "/var/lib/python-support/python2.5/gtk-2.0/gobject/constants.py", line 22, in <module>
    from _gobject import type_fr1:2.19.90-0ubuntu1om_name
ImportError: /var/lib/python-support/python2.5/gtk-2.0/gobject/_gobject.so: undefined symbol: _Py_ZeroStruct
Error in sys.excepthook:
Traceback (most recent call last):
  File "/var/lib/python-support/python2.5/apport_python_hook.py", line 36, in apport_excepthook
    from cStringIO import StringIO
ImportError: /usr/lib/python2.5/lib-dynload/cStringIO.so: undefined symbol: _Py_ZeroStruct

Original exception was:
Traceback (most recent call last):
  File "/var/lib/python-support/python2.5/gtk-2.0/gobject/__init__.py", line 30, in <module>
    from gobject.constants import *
  File "/var/lib/python-support/python2.5/gtk-2.0/gobject/constants.py", line 22, in <module>
    from _gobject import type_from_name
ImportError: /var/lib/python-support/python2.5/gtk-2.0/gobject/_gobject.so: undefined symbol: _Py_ZeroStruct

(nautilus:7546): Nautilus-Python-WARNING **: could not import gobject

Using nautilus-python 0.4.3-2, nautilus 2.19.90-0ubuntu1