+-------------------------
+autoconf & automake files
+-------------------------
+
+If you wish to change the `configure' script, the generated Makefile
+or other related files, you'll need to first install GNU m4, available
+from <ftp://ftp.gnu.org/pub/gnu/m4/>, then GNU autoconf
+(<ftp://ftp.gnu.org/pub/gnu/autoconf/>) and GNU automake
+(<ftp://ftp.gnu.org/pub/gnu/automake/>). Nmh is currently using a
+minimum of autoconf 2.61 and automake 1.10.
+
+Most of the configure-related files are automatically generated.
+The only files you should need to manually edit are configure.ac
+and any autoconf macros in the m4 directory. Don't, for instance,
+edit config.h.in. Though it is an input file from the point of
+view of the users (and the configure script) it is an output file
+from the point of view of the developers (and the autoconf script).