Comment 19 for bug 125131

Not sure if this helps, but the related bug report for Gentoo guys is here:
http://bugs.gentoo.org/show_bug.cgi?id=185141
The main reason is upstream changing the tarball without changing its name. Maybe people from Ubuntu and Gentoo could look at this issue together, because that's a common problem for both distros (and probably also Debian and others).