Mesa 9.0 no longer includes a copy of libGLU, it is instead available as
a separate tarball. To reflect this the packaging has been changed to
build mesa-libGLU as its own srpm; likewise for the GL manpages, since
both libGL-devel and libGLU-devel want to depend on them.
This change has already been built in F19, but for F18 that's this
errata right here: