mount -a doesn't obey "ro" in /etc/fstab

Hello!

   In order to test the new shiny msk driver, I've installed 6.2-PREPELEASE 
and then upgraded it to the CURRENT as of date=2006.09.26.00.00.00 (to 
overcome recent libalias breakage, and also to make sure that msk.HEAD.diff 
will apply cleanly). I've noticed the something very new (and annoying) after 
the upgrade: all filesystems listed in /etc/fstab with "ro" are still mounted 
as R/W. Here is my /etc/fstab:

# Device                Mountpoint      FStype  Options         Dump    Pass#
/dev/ad0s3b             none            swap    sw              0       0
/dev/ad0s4a             /               ufs     rw,sync         0       1
/dev/ad0s4e             /usr            ufs     rw              0       2
/dev/ad0s3a             /mnt3           ufs     ro              0       0
/dev/ad0s3d             /mnt3/usr       ufs     ro              0       0

and here is 'mount' output:

$ mount
/dev/ad0s4a on / (ufs, local, synchronous)
devfs on /dev (devfs, local)
/dev/ad0s4e on /usr (ufs, local, soft-updates)
/dev/ad0s3a on /mnt3 (ufs, local)
/dev/ad0s3d on /mnt3/usr (ufs, local, soft-updates)

I also can write under /mnt3, so 'mount' correctly shows FS status. mount
_does_ obey 'mount -ur /mnt3', it just ignores "ro" in /etc/fstab. Booting
into the single-user mode and making 'mount -a' has the same effect.
Is this breakage well-known, or something new?

Sincerely, Dmitry
-- 
Atlantis ISP, System Administrator
e-mail:  dmitry_at_atlantis.dp.ua
nic-hdl: LYNX-RIPE