Move from one server with 2.1.9 to another server with 2.2.3

[Martijn]

Hello all,

I have a old server with Suse 8.2 and Cyrus 2.1.9 and have setup new 
server with Suse 9.1 and cyrus 2.2.3.
Using imapcopy (disabled the seen-flag) I transfered the mailboxes. On 
the new server folders without messages/contents are not listed with 
listmailbox nor can I set ACL permissions, cyradm will return the 
message "Mailbox does not exist". Squirrelmail will not list the empty 
folders. Thunderbird shows the folders in light gray with italic fonts, 
it is not possible to subscribe to these folders.

My questions:
1. Is it possible to "recover" these folders/rights?

when not:
2. Can I use the xfer/xfermailbox cyradm command to move the mailboxes 
from 2.1.9 to 2.2.3?

when this is also not possible:
3. How to upgrade using the exist mailbox?
 I had a look at the /doc/install-upgrade.html doc but the section 
upgrading from 2.1.x all wasn't to clear to me. I think it is use full 
to upgrade the db since skiplist is faster.
There are files in the /var/spool/imap/ folder and mailbox.db in 
/var/lib/imap/ is do I only need to upgrade the mailboxes.db?

at last:
4. It would possible to do the tranfser again with the imapsynch script. 
But will it work with cyrus version 2.2.3?

Thank you in advance for any pointers they are appreciated since this is 
fairly new to me.
Martijn

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