sphinx abort: Could not import extension inheritance_diagram

[Timmie]

173 files written
Build API docs finished.
mkdir -p build/html build/doctrees
sphinx-build -b html -d build/doctrees source build/html
Running Sphinx v1.0 (hg)

Extension error:
Could not import extension inheritance_diagram (exception: cannot import name xfileref_role)
make: *** [html] Fehler 1

[Fernando Perez (fdo.perez)]

Sorry, this needs much more detail to be useful, because for me it works fine.

Please post a complete set of inputs leading to this error, along with ipython, sphinx, python version info and operating system details.