block/dk devices and lseek()

[RVP <rvp%SDF.ORG@localhost>]

Are block and dk* (wedge) devices supposed to support lseek()?
Because I see this on both -HEAD and 9.2_STABLE:

# Disks
#
$ sudo stat -f '%N: %z' /dev/rsd0
/dev/rsd0: 7849115648			# works
$ sudo stat -f '%N: %z' /dev/sd0
/dev/sd0: 0				# is this correct?

# Wedges
#
$ sudo stat -f '%N: %z' /dev/dk{0,1,2,3}
/dev/dk0: 0
/dev/dk1: 0
/dev/dk2: 0
/dev/dk3: 0
$ sudo stat -f '%N: %z' /dev/rdk{0,1,2,3}
/dev/rdk0: 0
/dev/rdk1: 0
/dev/rdk2: 0
/dev/rdk3: 0
$

# lseek(fd, 0, SEEK_END)
#
$ sudo ./a.out /dev/rsd0
7849115648
$ sudo ./a.out /dev/sd0
0

# wedges
#
$ sudo ./a.out /dev/rdk0
0
$ sudo ./a.out /dev/dk0
0

Thx,
-RVP