Case C-506/04: Judgment of the Court (Grand Chamber) of 19 September 2006 (reference for a preliminary ruling from the Cour administrative, Luxembourg) — Graham J. Wilson v Ordre des avocats du barreau de Luxembourg (Freedom of establishment — Directive 98/5/EC — Practice of the profession of lawyer on a permanent basis in a Member State other than that in which the qualification was obtained — Conditions for registration with the competent authority in the host Member State — Prior examination of knowledge of the languages of the host Member State — Remedy before a court or tribunal in accordance with domestic law)