[Bug-tar] Question re: incremental backup and directory rename detection

[Mike Cappella]

I'm curious about how tar is determining directory renames in 
incremental backups.  Is this by inode number, and the messages below 
are informative only?

From a strict name-only point of view, the rename detection below is 
incorrect (names of IMAP directories "new", "cur", and "tmp", after 
rename of any parent directories, would remain the same):

gtar: .../Maildir/.Archives/cur: Directory has been renamed from 
`.../Maildir/.Archives.2009/new'

gtar: .../Maildir/.Archives/new: Directory has been renamed from 
`.../Maildir/.Archives.2009/tmp'

gtar: .../Maildir/.Archives/tmp: Directory has been renamed from 
`.../Maildir/.Archives.2009'

If the messages are simply informative that the name previously 
corresponding to the inode is different across incremental backup runs, 
it seems there's nothing to worry about?

If you could help clarify, I'd appreciate it.
Thanks
--

     Mike