directing mail to shared folders

[Prentice Bisbal]

What is the best way to direct mail to a shared folder? For example, I 
need mail sent to deposit at ... to go to the shared folder deposit. The 
folder "deposit" is a top-level folder:

# /usr/local/cyrus/bin/cyradm -u cyrus localhost
Password:
localhost.localdomain> lm
deposit (\HasNoChildren)              user.prentice.Sent (\HasNoChildren)
user.prentice (\HasChildren)          user.prentice.Trash (\HasNoChildren)

When I try to subscribe to deposit, the folder appears under "Shared 
Folders" in the Subscribe dialog in my mail client (Mozilla 1.4), but 
when I try to subscribe, I get the error

"The current command did not succeed. The mail server responded: 
Subscribe: Mailbox does not exist."

The relevant log entries are

/var/log/imapd.log:
--------------------
Nov 26 16:51:27 pdb-pc-9 imapd[5589]: accepted connection
Nov 26 16:51:27 pdb-pc-9 master[6260]: about to exec 
/usr/local/cyrus-imapd-2.1.15/bin/imapd
Nov 26 16:51:27 pdb-pc-9 imaps[6260]: executed
Nov 26 16:51:27 pdb-pc-9 imapd[6260]: DBERROR db4: 21 lockers
Nov 26 16:51:27 pdb-pc-9 imapd[5589]: TLS engine: cannot load CA data
Nov 26 16:51:27 pdb-pc-9 imapd[5589]: starttls: TLSv1 with cipher 
RC4-MD5 (128/128 bits reused) no authentication
Nov 26 16:51:27 pdb-pc-9 imapd[5589]: login: 
bobblehead.rutgers.edu[128.6.178.121] prentice plain+TLS User logged in


/var/log/messages:
------------------
Nov 26 16:51:27 pdb-pc-9 imapd[6260]: DBERROR db4: 21 lockers
Nov 26 16:51:27 pdb-pc-9 imapd[5589]: TLS engine: cannot load CA data
Nov 26 16:51:27 pdb-pc-9 imapd[5589]: starttls: TLSv1 with cipher 
RC4-MD5 (128/128 bits reused) no authentication
Nov 26 16:51:27 pdb-pc-9 imapd[5589]: login: 
bobblehead.rutgers.edu[128.6.178.121] prentice plain+TLS User logged in

I have full access to this folder:

localhost.localdomain> lam deposit
prentice lrswipcd
anyone lrs
localhost.localdomain>

Finally, what do I need to do get mail directed there? Sending mail to 
deposit at ... doesn't work, and I don't want to make the mailbox user.deposit.

Thanks for your help.

Prentice