I did a quick search and didn't see this one covered. If I have the iPhone with 2.0 software synced to a Microsoft Exchange email account, synced as an Exchange account (not IMAP, not POP). Mail I read/unread on the iPhone shows up as read/unread on the desktop clients. This is expected behavior. Mail I read/unread on the desktop doesn't affect the status on the iPhone. This isn't good. It acts like an IMAP device when I read mail elsewhere and like a POP device when I read it from the phone.