There's no standard method for setting the major,
minor, and patchlevel versions in each module.  Some hardcode the
versions via #defines; others base them on the autoconf-defined value of
PACKAGE_VERSION.

It would make a lot more sense to have autoconf handle defining these,
and base it off PACKAGE_VERSION (for those who don't do much autoconf,
PACKAGE_NAME and PACKAGE_VERSION are automatically set in config.h based
on the values passed to AC_INIT() in configure.ac).  The variable names
I've chosen to go w/ are PACKAGE_VERSION_MAJOR, PACKAGE_VERSION_MINOR,
and PACKAGE_VERSION_PATCHLEVEL.

I've described the problem, proposed patches, gotten feedback, and revised the
patches here:

http://lists.freedesktop.org/archives/xorg/2006-October/018505.html