Customizing Office Language Settings
The first time a Microsoft Office 2003 application starts up, Office 2003 applies default language settings that match the language version of Office that you have installed on the computer and the language of the operating system.
Administrators can configure these language settings in advance rather than using the default settings. If you specify custom language settings when you install Office (for example, in a transform), then Office detects that language settings are already defined and does not overwrite your settings with the default settings when users start the applications.
Four primary language settings affect the way users work with Office:
Installation language Default language for Office applications ...