Thanks for your reply, just to complete this conversation, I get the following error message:

{'error': {'*': 'See https://www.wikidata.org/w/api.php for API usage',
           'code': 'no-direct-editing',
           'info': 'Direct editing via API is not supported for content '
                   'model wikibase-item used by Q5972069'},
 'servedby': 'mw1119'}


Undo with the webinterface works, both as a logged in and anonymous user. Will tinker around a little, if I do not find a solution, I will file a bug report.

Best,
Sebastian


>
> Am 11.11.2015 um 04:08 schrieb Sebastian Burgstaller:
> > The undo and undoafter API calls do not seem to work on Wikidata items.
>
> That should work. If it doesn't, please file a bug report, and list some
> revisions you tried to undo.
>
> Please check if you are able to undo the edit manually over the normal user
> interface, too.
>
>
> --
> Daniel Kinzler
> Senior Software Developer
>
> Wikimedia Deutschland
Gesellschaft zur Förderung Freien Wissens e.V.