I would assume that this is supported, but no idea for sure. I'm attempting to import a resources calendar into the new Zimbra resource mailbox. The 2 resources that need to be imported are assigned to an admin user (the user has their personal mailbox plus 2 more). Whenever I select either of the 2 resource mailboxes, the migration wizard crashes right away. If I select the "real" users mailbox, the wizard will continue. Nothing is logged in the migration logs except for the wizard version. I did get the attached error report from drwatson though.
BTW, I'm running ZCS 4.5.5GA with migration wizard 4.5.5GA 881.