Virtual Tape shared between guest partitions

Hi Guys

I don't know if this is possible or not, but I would like to share a
virtual tape drive between partitions if possible.

The set up is an an IBM i V7R1 TR7 partition hosting a couple of V6R1 guest
partitions. The client does some saves on one of the guest partitions that
are transferred onto another guest partition. The way the transfer was set
up was to implement virtual tape on the guest and save to virtual tape,
after which the library is restored back to the guest with a new name then
SAVRST'd across to the other guest. All the partitions are connected via
SNA using EE.

The save to virtual tape is also used for point in time recovery for the
application if required, so it can't just be copied when the save happens.
Ultimate goal is to get a copy of a library in the point in time save onto
another partition.

What would be useful is if I could alter the save to have the point in time
save taken to virtual tape on the hosting partition. I would then be able
to restore from that save to any of the guest partitions on that host
without requiring additional storage or extra restores or transfer
processes.

I created an image catalog type *TAP on the hosting partition but was not
able to see a corresponding tape device on the guest partitions as I would
expect to with a real tape device or an optical device (real or virtual).
The virtual tape (there is only one) is mounted in the image catalog and
the image catalog is loaded into a virtual tape drive.

Is this actually possible or is it a virtualisation limitation, or an issue
with the guests being at V6R1. I have not had any success finding any
documentation specific to sharing virtual tape between guest partitions,
and the set up looks OK to me. I've been able to use type *OPT image
catalogs mounted on the host between guest partitions without creating
multiple copies, so I think I probably have that set up right.

Any suggestions or advice welcome.