Mesa-devel-3.3 does not include the man pages for the GLUT library. Within the glut tarball they're in man/glut/
Which glut tarball are you speaking of ? We use the Mesa tarball from www.mesa3d.org with no supplementary packages. There are no glut manpages in this tarball at all, therefore we don't ship them.
the GLUT tarball at http://reality.sgi.com/mjk/glut3/glut-3.7.tar.gz for example. I'll file a report with the Mesa people.