"hg push" raises exception in "changegroup.csetlog" hook

When I run "hg push" on my machine, an exception is reported. This has happened every time (about 4 times) when pushing my "Impeller" repo. The exception does not seem to break anything; my changes are uploaded and visible. I believe the exception has always been exactly the same.

I've only been using Bitbucket for about a week, following 3 months of not using it, and I have not seen this problem before.

{{

{\\ $ hg push\\ pushing to https://holmak@bitbucket.org/holmak/impeller\\ searching for changes\\ http authorization required\\ realm: Bitbucket.org HTTP\\ user: holmak\\ password:\\ remote: adding changesets\\ remote: adding manifests\\ remote: adding file changes\\ remote: added 3 changesets with 9 changes to 5 files\\ remote: error: changegroup.csetlog hook raised an exception: 'NoneType' object has no attribute '_repo'\\ }}

}