Tape drive busy

[Brad Crotchett]

Can anyone tell me what usually causes this?

[root at ray log]# mt -f /dev/st0 rewind
/dev/st0: Device or resource busy

The drive is plugged in, has a tape in it, and nothing is using it. 
Unfortunately, my log rotation issue (and yes that is still going on)
cut off my dmesg, but this is the last line of it:

Attached scsi tape st0 at scsi4, channel 0, id 6, lun 0

This is the output from lsmod:

Module                  Size  Used by
eepro100               18128   1
ipt_LOG                 4064   1  (autoclean)
ipt_state               1152   1  (autoclean)
ip_conntrack           18668   1  (autoclean) [ipt_state]
iptable_filter          2272   0  (autoclean) (unused)
ip_tables              11968   3  [ipt_LOG ipt_state iptable_filter]
st                     27092   1
ext3                   65728   2
jbd                    44580   2  [ext3]
aic7xxx               114784   1
aacraid                24948  10
sd_mod                 11900  10
scsi_mod              101592   4  [st aic7xxx aacraid sd_mod]

Thanks in advance,

Brad