Comment 2 for bug 480913

This is because sphinx is in main, and .mo file are stripped out put in language-pack-* packages. As a work-a-round for building locally, make sure you have the desired one installed. The original reporter's case that is language-pack-nl-base.

This causes a problem for any package that build depends on sphinx trying to build documentation in multiple locales. We're hitting this with the Ubuntu Packaging Guide. See bug 943154.

David Planella seems to think that we might be able to get sphinx excluded from the .mo file stripping and suggests talking to pitti.