Joined Cases C-396/05, C-419/05 and C-450/05: Judgment of the Court (Grand Chamber) of 18 December 2007 (Reference for a preliminary ruling from the Sozialgericht Berlin and Landessozialgericht Berlin-Brandenburg — Germany) — Doris Habelt (C-396/05), Martha Möser (C-419/05) and Peter Wachter (C-450/05) v Deutsche Rentenversicherung Bund (Social security — Regulation (EEC) No 1408/71 — Annexes III and VI — Freedom of movement for persons — Articles 18 EC, 39 EC and 42 EC — Old-age benefits — Periods of contribution completed outside the Federal Republic of Germany — Not exportable)