AC_PREREQ comes first in autoscan

[NightStrike]

Using autoconf 2.63 and autoscan, my automatically generated
configure.scan has AC_PREREQ as the first macro in the file, and
AC_INIT second.  The autoconf manual has this to say about it:

"This macro is the only macro that may be used before AC_INIT, but for
consistency, you are invited not to do so."

If the manual says "please don't do it," why does autoscan do it?