netbsd-5 named chroot tree confusion

[Chris Ross <cross+netbsd%distal.com@localhost>]

  This is about netbsd-5, not netbsd-current, but...

  The /var/chroot/named tree, which includes on current both of 
/var/chroot/named/etc/namedb/cache, and 
/var/chroot/named/etc/namedb/keys.  However on my netbsd-5 build, it 
contains only the 'cache' directory, and not the keys directory.  For a 
clean destdir, when nbmtree runs, it reports (amongst all other output):

missing: ./var/chroot (created)
missing: ./var/chroot/ftp-proxy (created)
missing: ./var/chroot/named (created)
missing: ./var/chroot/named/dev (created)
missing: ./var/chroot/named/etc (created)
missing: ./var/chroot/named/etc/namedb (created)
missing: ./var/chroot/named/etc/namedb/cache (created)
missing: ./var/chroot/named/usr (created)
missing: ./var/chroot/named/usr/libexec (created)
missing: ./var/chroot/named/var (created)
missing: ./var/chroot/named/var/run (created)
missing: ./var/chroot/named/var/tmp (created)

  However, the src/etc/mtree/special file in my netbsd-5 source tree 
contains:

./var/chroot/named              type=dir  mode=0755
./var/chroot/named/dev          type=dir  mode=0755
./var/chroot/named/etc          type=dir  mode=0755
./var/chroot/named/etc/namedb   type=dir  mode=0755
./var/chroot/named/etc/namedb/cache     type=dir mode=0775 uname=named 
gname=named
./var/chroot/named/etc/namedb/keys      type=dir mode=0775 uname=named 
gname=named
./var/chroot/named/usr          type=dir  mode=0755
./var/chroot/named/usr/libexec  type=dir  mode=0755
./var/chroot/named/var          type=dir  mode=0755
./var/chroot/named/var/run      type=dir  mode=0775 gname=named
./var/chroot/named/var/tmp      type=dir  mode=01775 gname=named


  So, there seems to be a disconnect somewhere.  Anyone know where?  
This is causing my /etc/security run to complain about the missing 
directory on my production netbsd-5 machine, and I'm just trying to 
figure out the "correct" way to clean it up.

  Thanks...

                                     - Chris