Any connections to the the Island of "Malo" in Oceania and the island on LOST? Mythology* on the island of Malo includes the "belief in dual souls, one of which goes to an afterworld usually situated either on an island or underground while the other takes on various forms."
http://www.janeresture.com/melanesia_myths/Vanuatu.htm

Also were any of the writers aware of the Australian show "The Lost Island" when writing the pilot for LOST? I figured similarities could be coincidental.
http://www.australiantelevision.net/lostislands.html
;)