I've noticed Outlook Zimbra connector users have their delivery name headers changed.
for example, before we were running zimbra just POP3 iMail the header looked like this
From: Tom Sawyer <email@example.com>
To: 'Mark Warner' <firstname.lastname@example.org>
So within Outlook the inbox would display the person's name, not their email address.
To: "'Mark Warner'" <email@example.com>
I've gotten a number of complaints since our rollout regarding this. Apple Mail users are just fine when sending as they aren't using the ZConnector.
Any ideas? or perhaps a bugzilla entry?