We have people using Nokia e72 devices with zimbra mobile (Mail for exchange). What happens is that after some time the users are not able to sync anymore (they don't receive e-mails). I checked sync.log and there are messages like this: "sync - SyncState: client stuck on item=0; skip and end itemized mode" and "sync - SyncState: client stuck on version=1; start itemized mode" in the moments they try to sync. The only solution is to delete the account from the phone and create it again/resyncing everything. Also this users are not being able to send e-mails (a lot of people complain on this also as you can check at Nokia E52 Zimbra),
Please help us,
Our users are very unhappy and asking for an alternative..