Adhoc Reporting's user interface is internationalized to support users whose preferred language is not English. If you would like to localize Adhoc Reporting for your preferred locale, follow these steps:

We encourage members of the Pentaho Community to participate in the localization of Adhoc Reporting and the BI platform, and contribute your localization work back to the Pentaho Community.

You may find it useful to download and run Quick Locale Switcher, which is a useful add-on for changing Firefox's language settings while debugging your localization code.