I have to copy Zimbra from a vserver to new vserver but same domain and IP.

I create a new vserver on Debian Lenny, install from srcatch the same Zimbra version and then make a rsync copy of /opt/zimbra (old) to /opt/zimbra (new).

Then I shutdown the old vserver and run the new vserver with same domain and same IP. It seems work mails sent/received well inside domain and outside but in Admin console I got an error in queue file all tabs are marked (error) a refresh scan and I got an error panel with:

Mail : system failure: exception during auth {RemoteManager: zimbra.geismar.com->zimbra@zimbra.geismar.com:22} Code d'erreur : service.FAILURE Method: GetMailQueueInfoRequest Détails :soap:Receiver
How fix it ?