there are so many dependencies to gettext, which are not really
	necessary.  for example, devel/bison builds just fine even if we
	remove dependency to gettext.  devel/bison will fall back to:
	- use libintl shipped with bison itself
	- use pre-generated po/*.gmo files (msgfmt is not required)

	for the former point, it may be important to depend onto devel/gettext,
	as devel/gettext includes some security fixes.  actually we now have
	/usr/lib/libintl.a, and we should be using that if we have one
	(somehow gettext.m4 will not fall back to pre-installed
	/usr/lib/libintl.a correctly, which is another problem)

	for the latter, devel/gettext is not necessary, or at least
	devel/gettext should be visited by BUILD_DEPENDS (not DEPENDS).

	i'm not sure how to solve the former point.  if configure script in
	devel/bison is clever enough to fall back to /usr/lib/libintl.a,
	we should need the following lines only:
		LIBINTL=	yes
		BUILD_DEPENDS+=	msgfmt:../../devel/gettext
	but at this moment, those configure scripts do not do the right thing.

	another option is to have --disable-nls.

itojun