I have been using the iTouch with Zimbra mobile and it looks great. I can send email and look at my appointments. There are a couple issues I'm experiencing.
1. How the heck do I add an appointment? There is a button to compose a new message, but there are only buttons for the type of "view".
2. The color of the calendar does not display. My appointment just "whites" out the time span. No color block.