Note: @Jerry928 requested that we use Timor-Liste as the country name. The official JetPunk name is still East Timor and, as always, both answers will be accepted.
Because the International Organization for Standardization (ISO) official short form in English and all other languages for the country is Timor-Leste, which has been adopted by the United Nations, the European Union, and the national standards organisations of France (AFNOR), United States (ANSI), United Kingdom (BSI), Germany (DIN), and Sweden (SIS), all diplomatic missions to the country by protocol, and the CIA World Factbook. The official names of Timor-Leste in the country's three official languages are Democratic Republic of Timor-Leste (English), República Democrática de Timor-Leste (Portuguese), and Repúblika Demokrátika Timór-Leste (Tetum).
To date, this one has had me stumped. I've looked and looked at that previously, even to the extent of emailing the Bahrain Givernment to ask if Passport Island really is bisected by the country border, or whether Passport Island lies wholly in Saudi or Bahraini territory. If anyone can get a definitive answer please send it through!!!
Surely it can't be too different from a bridge, not considered a border. Other man-made features aren't considered in these kinds of data either, which is why Jutland isn't really an island, even though it is technically split via canal. At least those are my thoughts.