Union mounting on a union mount

["D'Arcy J.M. Cain" <darcy%NetBSD.org@localhost>]

I have an odd situation.  Here is an excerpt from my fstab:

/usr/pkg/etc/asterisk      /usr/local/etc/asterisk     null    rw
/VEX/etc/asterisk          /usr/local/etc/asterisk     union   rw
/usr/local/var/asterisk    /usr/local/etc/asterisk     union   rw

Basically I create an empty directory for my asterisk config.  I
first null mount the distributed files on that so that the pkg files
are still accessible.  Then I union mount my locally modified (and
subversioned) files over that.  Finally I union mount the directory
where generated files are created over that.  This scheme keeps
everything nicely compartmentalized.

My problem is that the final mount does not work at boot time.  If I
run "mount /usr/local/var/asterisk" after the system has booted it
mounts just fine.  Also "mount -a" does not do the final mount.  Am I
missing something or am I just pushing the limits?

-- 
D'Arcy J.M. Cain <darcy%NetBSD.org@localhost>
http://www.NetBSD.org/ IM:darcy%Vex.Net@localhost