I've repeated the tests with LSUB "" *. I think there's a problem with
setting the namespace prefix.
telnet imap.xx.yy 143
1 LOGIN user password
2 LSUB "" * => shows INBOX
Sent
Trash
folderAA
shared/UserB/folderXX
3 LSUB "" * => shows shared/UserB/INBOX
shared/UserB/folderXX
Sent
Trash
folderAA
4 LSUB "" * => shows shared/UserB/INBOX
shared/UserB/folderXX
Sent
Trash
folderAA
This behavior is reproducable. Please note that the mailboxes of the
shared namespace are listed first and the own inbox of the user disappears.
Holger