After using Network Image Utility to create an installation image with a specific default language, the default time zone and input menu settings set by the installer may be incorrect; they do not match the settings for your region.
This happens because Mac OS X sets Pacific (Cupertino, CA) as the default time zone location and the United States as the region format regardless of what the default language is selected for the network install.
For managed client users, the client will assume the same localized settings as the language Mac OS X Server was installed with. For unmanaged systems or other situations in which the locale needs to be set automatically, preconfigure a Mac OS X client with the desired locale and then create a Network Install image from that client system.