[White]

# sysctl kern.securelevel
kern.securelevel=2

# ls -l /dev/{,r}wd0?
crw-r----- 1 root operator 3, 0 Jan 18 2009 /dev/rwd0a
crw-r----- 1 root operator 3, 1 Jan 18 2009 /dev/rwd0b
crw-r----- 1 root operator 3, 2 Jan 18 2009 /dev/rwd0c
crw-r----- 1 root operator 3, 3 Jan 18 2009 /dev/rwd0d
crw-r----- 1 root operator 3, 4 Jan 18 2009 /dev/rwd0e
crw-r----- 1 root operator 3, 5 Jan 18 2009 /dev/rwd0f
crw-r----- 1 root operator 3, 6 Jan 18 2009 /dev/rwd0g
crw-r----- 1 root operator 3, 7 Jan 18 2009 /dev/rwd0h
crw-r----- 1 root operator 3, 8 Jan 18 2009 /dev/rwd0i
crw-r----- 1 root operator 3, 9 Jan 18 2009 /dev/rwd0j
crw-r----- 1 root operator 3, 10 Jan 18 2009 /dev/rwd0k
crw-r----- 1 root operator 3, 11 Jan 18 2009 /dev/rwd0l
crw-r----- 1 root operator 3, 12 Jan 18 2009 /dev/rwd0m
crw-r----- 1 root operator 3, 13 Jan 18 2009 /dev/rwd0n
crw-r----- 1 root operator 3, 14 Jan 18 2009 /dev/rwd0o
crw-r----- 1 root operator 3, 15 Jan 18 2009 /dev/rwd0p
brw-r----- 1 root operator 0, 0 Jan 18 2009 /dev/wd0a
brw-r----- 1 root operator 0, 1 Jan 18 2009 /dev/wd0b
brw-r----- 1 root operator 0, 2 Jan 18 2009 /dev/wd0c
brw-r----- 1 root operator 0, 3 Jan 18 2009 /dev/wd0d
brw-r----- 1 root operator 0, 4 Jan 18 2009 /dev/wd0e
brw-r----- 1 root operator 0, 5 Jan 18 2009 /dev/wd0f
brw-r----- 1 root operator 0, 6 Jan 18 2009 /dev/wd0g
brw-r----- 1 root operator 0, 7 Jan 18 2009 /dev/wd0h
brw-r----- 1 root operator 0, 8 Jan 18 2009 /dev/wd0i
brw-r----- 1 root operator 0, 9 Jan 18 2009 /dev/wd0j
brw-r----- 1 root operator 0, 10 Jan 18 2009 /dev/wd0k
brw-r----- 1 root operator 0, 11 Jan 18 2009 /dev/wd0l
brw-r----- 1 root operator 0, 12 Jan 18 2009 /dev/wd0m
brw-r----- 1 root operator 0, 13 Jan 18 2009 /dev/wd0n
brw-r----- 1 root operator 0, 14 Jan 18 2009 /dev/wd0o
brw-r----- 1 root operator 0, 15 Jan 18 2009 /dev/wd0p

Did you happen to make any local changes to src/sys/arch/i386/conf/GENERIC?

Yes, but not much.