A compact gas discharge lamp (301) comprising four (or more) interconnected tube segments (11, 12, 13, 14) is provided with an external electrode (310) that extends at least throughout the length of the tube segments and that is in contact with all tube segments. Several embodiments of the external electrode are disclosed. The external electrode is preferably connected to a node (C) midway between the lamp electrodes, to which end a capacitive divider (441, 442) is arranged in parallel with the lamp.