bug-notice when trying to export a notebook

zim 0.54-1
xubuntu 11.10

I found out that there is a version 0.54-1. I installed it today. With the new version the export-dialog doesn't start, but I get the following bug message:

<<
This is zim 0.54
Python version is sys.version_info(major=2, minor=7, micro=2, releaselevel='final', serial=0)
Gtk version is (2, 24, 6)
Pygtk version is (2, 24, 0)
Platform is posix
No bzr version-info found

======= Traceback =======
  File "/usr/lib/pymodules/python2.7/zim/gui/__init__.py", line 820, in _action_handler
  File "/usr/lib/pymodules/python2.7/zim/gui/__init__.py", line 1514, in show_export
ImportError: No module named exportdialog