Zim 0.61: sourceview plugin: AttributeError: 'MainWindowExtension' object has no attribute 'ui'

Running Linux Mint 13 (Ubuntu LTS 12.02). Getting following error when trying to insert a code block:

This is zim 0.61
Platform: posix
Locale: en_US UTF-8
FS encoding: UTF-8
Python: (2, 7, 3, 'final', 0)
Gtk: (2, 24, 10)
Pygtk: (2, 24, 0)
No bzr version-info found

======= Traceback =======
  File "/usr/lib/pymodules/python2.7/zim/actions.py", line 55, in func
    self.func(instance, *arg, **kwarg)
  File "/usr/lib/pymodules/python2.7/zim/plugins/sourceview.py", line 108, in insert_sourceview
    lang = InsertCodeBlockDialog(self.ui).run() # XXX
AttributeError: 'MainWindowExtension' object has no attribute 'ui'

Getting similar message when running in debug mode:

DEBUG: Action: insert_sourceview
ERROR: Exception during action: insert_sourceview
Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.7/zim/actions.py", line 55, in func
    self.func(instance, *arg, **kwarg)
  File "/usr/lib/pymodules/python2.7/zim/plugins/sourceview.py", line 108, in insert_sourceview
    lang = InsertCodeBlockDialog(self.ui).run() # XXX
AttributeError: 'MainWindowExtension' object has no attribute 'ui'
DEBUG: Running ErrorDialog