tar on -current does not work with my Buslogic BT445S and Archive Viper 150.

Here's the output:

tip-mp4-ncs-1# tar -xvf /dev/rst0 stuff
tar: read error on /dev/rst0 : Input/output error

Here's dmesg output:

NetBSD 0.9a (ELSIE-SD) #1: Sat Apr 23 22:07:27 PDT 1994
  dhess@tip-mp3-ncs-11.stanford.edu:/usr/src/sys/arch/i386/compile/ELSIE-SD
CPU: i486DX (486-class CPU)
real mem  = 24772608
avail mem = 22220800
using 328 buffers containing 1343488 bytes of memory
pc0 at isa0 port 0x60-0x6f irq 1: color
com0 at isa0 port 0x3f8-0x3ff irq 4: ns82450 or ns16450, no fifo
com1 at isa0 port 0x2f8-0x2ff irq 3: ns16550a, working fifo
lpt0 at isa0 port 0x3bc-0x3c3 irq 7
wdc0 at isa0 port 0x1f0-0x1f7 irq 14
wd0 at wdc0 drive 0: 325MB 1010 cyl, 12 head, 55 sec <WDC AC2340>
fdc0 at isa0 port 0x3f0-0x3f7 irq 6 drq 2
fd0 at fdc0 drive 0: 1.44MB 80 cyl, 2 head, 18 sec
bt0 at isa0 port 0x330-0x333 irq 11: version 3.3, sync, parity, 16 mbxs
scsibus0 at bt0
bt0 targ 0 lun 0: <CONNER  CP30540 545MB3.5AFBD> SCSI2 direct fixed
sd0 at scsibus0: 520MB, 2242 cyl, 6 head, 79 sec, 512 bytes/sec
bt0 targ 2 lun 0: <ARCHIVE VIPER 150  21247-005> SCSI1 sequential removable
st0 at scsibus0: rogue, density code 0x0, 512-byte blocks, write-enabled
bt0 targ 4 lun 0: <NEC     CD-ROM DRIVE:4001.0 > SCSI2 readonly removable
cd0 at scsibus0: cd present, 126271 x 2048 byte records
npx0 at isa0 port 0xf0-0xff: using exception 16
biomask 4840 netmask 0 ttymask 1a
st0(bt0:2:0): illegal request
st0: cannot set selected mode
st0: bad request, must be between 0 and 0

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