Thank you Kurt,
The production system is TSM 5.3 that should be replaced by 6.2 gradually.
There is currently one tape drive, so impossible to have dedicated libraries
for old and new system.
As older version cannot be the library manager, what do you think if new TSM
becomes library manager server and provides library functionality to old
TSM? Can old TSM switch to a new shared library that owns by new TSM?

Let me pose the question in a more precise manner:
Can an operational TSM system switch from dedicated library to a shared one
(served by another server)? Evidently the main concern is to keep current
tape volumes, backup data and TSM database intact.

Thank you,
Mehdi