We’ve got a zimlet for that!
The great thing about Zimbra is that it lets users do a lot of customization. There are a lot of features that can be turned on and off based on user preferences. Several features are exposed in the form of “Zimlets” – tiny modules that are designed to do a specific task such as send you a daily summary of your appointments for the day or help you connect to WebEx.
Check which Zimlets are available to you.
Go to Preferences->Zimlets (on the Left Pane). Turn on/off Zimlet of your choice