st32 errors in /var/adm/messages

I'm trying to find out why st32 type errors keep arriving in /var/adm/messages (and are sent almost every day to my inbox by a Log Alert auto email).

Can anyone tell me if there's a problem with the tape device?

I'm seeing the following about 3 times a week, just after the backup to tape starts and one second before it finishes.

/var/adm/messages:Jul 6 06:34:52 ukpsprod1 unix: st32: <Sun DLT7000>
/var/adm/messages:Jul 6 06:34:52 ukpsprod1 unix: st32 at SUNW,fas1:
/var/adm/messages:Jul 6 06:34:52 ukpsprod1 unix: target 4 lun 0 /var/adm/messages:Jul 6 06:34:52 ukpsprod1 unix: st32 is /sbus@7,0/SUNW,fas@3,8800000/st@4,0

Thanks