> AFAIK, OpenBSD's M4 is enhanced to be compatible with GNU M4 and
> enough to be able to run Autoconf. (I've never tried, but saw a commit
> message saying such a thing.)

The log message mensioning this.

  http://www.openbsd.org/cgi-bin/cvsweb/src/usr.bin/m4/eval.c?rev=1.26&content-type=text/x-cvsweb-markup

---                                                  \||v,
A Fish Lover,                                       /     \<
    Masao Uebayashi                               ((.),    |
        <uebayasi@soum.co.jp>                     ==__}|__ |
                                                   // \| |/
                                                        /|