Accessory Dwelling Units have been included in the proposed revisions to the Oahu General Plan:
http://www.honoluludpp.org/Portals/0/pdfs/planning/generalplan/PubRevDraft_Part2_Nov2012.pdf
Page 55 of 102, Housing Policy 13, states "Encourage the production and maintenance of affordable rental housing, ohana housing, and accessory dwelling units."
Underlined potions are to be added to the Plan. The rational given for
the change is that "Ohana and accessory units provide the opportunity to
increase the housing stock."