Zimbra Collaboration Server (ZCS) Open Source and Network Editions are available in multiple languages. For a complete list of languages available for Zimbra, refer to the "Available Languages" section of the System Requirements document.
Each ZCS Open Source and Network Edition ships with English enabled by default. Administrators can easily change the default language by setting new default for a given Class of Service (CoS). End-users can override any default language settings and choose their own simply by changing their language preferences.
Administrators can also add their own languages to ZCS, either ones from the Community or their own modifications. To find out more about getting new ZCS translations, understanding the process, and more visit the Language Wiki page.
If you have questions or would like to provide feedback on a translation (official or unofficial) we encourage you to use the Zimbra Forums.