We've run into a very strange problem with ZCS 5.0.7 and iPhone sync. A user reset his iPhone, and afterward isn't able to get any mail. Contacts and calendar seem to sync. A folder list is shown, but no mail in any folder.
If we set up a different Zimbra user on the same phone it works. Details are in
bug #30731 (marked private due to sync.log containing email snippits)
Anyone else seen something like this?