+There is a difficulty with empty directories in source packages. git
+refuses to handle empty directories - they tend to just vanish from
+commits and checkouts. But I'm told there are some source packages
+whose orig tarballs contain empty directories, and build systems
+depend on those empty directories.
+
+Currently if you dgit clone such a package, it won't build. I don't
+have a particularly good answer to this problem right now. It's no
+good to have dgit create these directories in the working tree, when
+it notices, because the git branches might be transported by plain git
+and used elsewhere.
+
+This can be worked around in the source package by either adding
+something to debian/rules to create these directories, or by adding
+some files to the directories to make them nonempty. But at the
+moment a maintainer is not required to do either of these things.