period data type

Hello,

Is anyone working on a period data type as described in Dr. Richard Snodgrass' 
book _Developing Time-Oriented Database Applications in SQL_[1]? I did not 
see a relevant project listed in the TODO. I would like to contribute 
(possible funding and/or coding) the development of a conforming 
implementation of this data type.

[1]http://www.cs.arizona.edu/~rts/tdbbook.pdf

Thanks,
wt
-- 
Warren Turkal (w00t)