I routinely use multiple systems to read and manage IMAP email. When I read and clean up email on one system and then move to another system, those changes follow me.
With Zimbra, when I use IMAP on the account, my inbox email and clean ups aren't reflected in the Zimbra web mail view of my email.
This seems wrong. What if I file the email from the web UI into different folders then when I sorted email with IMAP, are two copies of the message created? What about all the messages I deleted in IMAP but are still there in the web UI.
As it stands now, the difference between IMAP and the web UI is like reading POP mail from two different systems, and we all know that is why we moved to IMAP in the first place!