no attribute 'dependency_has_changed' error

[leodumont]

Hello,
I'im trying to run dj-nested-inlines in Django 1.7.11 with python 2.7.9, the forms are displaying very well but I've a no attribute error when trying to add or edit a record from the admin :
Exception Type: AttributeError
Exception Value: 'Editeurs_editionsForm' object has no attribute 'dependency_has_changed'
Exception Location: /usr/local/lib/python2.7/dist-packages/src/dj-nested-inlines/nested_inlines/forms.py in dependency_has_changed, line 35

Any clue on this problem ?
Thanks,