Good afternoon Gábor,
GH> The translation of the admin part and the front end of Drupal are not GH> separated. Drupal by its nature handles translation on a text by text GH> basis. If the text "Save" needs translation, regardless of where it GH> shows up, it will be displayed translated, if a translation is GH> available in the given language. Admin or front end alike. The GH> localization update module downloads and manages translations from GH> localize.drupal.org, and keeps track of your own modifications.
Ah, that explains a lot :-)
Tnx