NAT_FILE always required?

[Mark Kettenis]

It looks as if I'm ready to get rid of NAT_FILE for *BSD/amd64.
Except there's this funny bit of code in configure.in:

if test "${nativefile}" = ""; then
        < Makefile \
        sed -e '/^NATDEPFILES[[ 	]]*=.*\\$/,/[[^\\]]$/s/^/# /' \
            -e '/^NATDEPFILES[[ 	]]*=/s/^/# /' \
        | sed -e '/^\(NATDEPFILES[[ 	]]*[[+]]=[[ 	]]*\)/s//# \1/' \
	> Makefile.tem
mv -f Makefile.tem Makefile
fi

This code comments out the definition of NATDEPFILES if NAT_FILE isn't
there.  What's the purpose of this code?  Can anybody see a reason why
this code can't be deleted?

Mark