it's probably out of date (last change 2009).
If you just want mesa there's no voodoo involved:
you may have to adjust the "--libdir" parameter and more config arguments are available to enable (experimental) features (see ./autogen.sh --help).
git clone git://anongit.freedesktop.org/mesa/mesa
./autogen.sh --prefix=/usr --libdir=/usr/lib64 --with-gallium-drivers="<drivername>"
make install (<-- this will overwrite your packages installed by your package manager, in case you want to use the result system wide)