Maybe not quite a bug, and maybe not your fault, but configure apparently picks the first program called "gm4" in my path, >not< the first appropriate m4 or gm4.
My problem is that Sun provides a "gm4" that is old and makes nearly all the bison tests fail. I have installed a much newer one as "m4" (what it installs as by default, of course), which is much earlier in my path and works fine. Yes, I can tell it which m4 to use, but the canonical name >is< "m4", so that seems wrong. And yes, I can make (and have now made) a link to my m4 called "gm4", but the program's name is "m4", and I think the detection should be smarter, especially since it really is version-sensitive. Thoughts? ab