Hawaiian short dates actually use Roman numerals. For example, March 9, 2004
should be 9/III/2004. This is a shortcoming in the current haw_US locale.
It's possible that this need could be served by the new "very abbreviated" month
data. If not, there would need to be support for having a RBNF format for a
numeric field. This could be useful in other circumstances, e.g. the use of
Roman numerals in media copyrights (e.g. ©MMIV).