Hi,
I'm fairly sure that tape is one of those things like audio cds that you cannot mount into the vfs - the backup software, including commands like 'tar', just seems to work without it. You can do
mt -f /dev/st0 status
to query the status of your tape drive
tar cvft /dev/st0 /home/joeuser
(to backup your /home/joeuser)
mt -f /dev/st0 rewind
mt -f /dev/st0 eject
(See 'man mt', 'man tar', etc)
However if you really want to try to mount it in the way you would with a disk partition, you could always have a go at the following (I don't think it will work though !) :
Firstly, you would need to create a mount point in you filesystem (I tend to use the device name as a subdirectory of /mnt but it could be any directory you like...
mkdir /mnt/st0
Then attempt to mount the device to that mount point using 'auto' unless you happen to know the specific filesystem format...
mount /dev/st0 -t auto /mnt/st0
It will soon tell you if it can't recognise the filesystem.. Howeever, in this case I believe it will just tell you it can't mount a non-block device !
Rgds, Iain