Odd warning

[Ralf Corsepius]

Hi,

After having upgraded from automake-1.8.1 to automake-1.8.2 (And having
modified some Makefile.ams), I received this warning from automake:

configure.ac:16: version mismatch.  This is Automake 1.8.2,
configure.ac:16: but the definition used by this AM_INIT_AUTOMAKE
configure.ac:16: comes from Automake 1.8.1.  You should recreate
configure.ac:16: aclocal.m4 with aclocal and run automake again.
WARNING: `automake-1.8' is probably too old.  You should only need it if
         you modified `Makefile.am', `acinclude.m4' or `configure.ac'.
         You might want to install the `Automake' and `Perl' packages.
         Grab them from any GNU archive site.
 cd . && /bin/sh ./config.status Makefile

I don't understand why this warning is issued.

To my understanding automake-1.8.1 and automake-1.8.2 both should
implement the automake-1.8 API and therefore should be sufficiently
compatible.

Therefore, I don't understand why 
1. this warning is required at all.
2. automake doesn't automatically try to do what it recommends the user
to do manually: running aclocal and automake.

Ralf