Remote tunefs -n enable

[MC]

Hello again

I have another issue on the same box.  The bloke who installed FreeBSD 6.0onto
the machine is a linux man.  He didn't know about softupdates nor apparently
does
he know yet about option 4 [read only singule user mode] on the bootloader.

Consequently he hasn't set softupdates on the main '/' partition

On Freebsd 4.x from ssh2 I used to:

mount -fr /dev/ad0s1a /
tunefs -n enable /dev/ad0s1a
mount /dev/ad0s1a /

but attempting this on FreeBSD 6.x immediately locks up the machines when in
multiuser mode.
On a workstaion I then tried to sneak tunefs into the first lines of
/etc/rc.  Unfortunately it seems that
'/' is read/write mounted before /etc/rc runs, so the tunefs just makes an
error and the box boots up
again without softupdates.  My question then is how to go about getting the
tunefs line in a startup
script, before the disk is mounted read/write and with realtime access only
in multiuser mode by telnet/ssh2.

Or perhaps there is another means, this being BSD?