Whitewater Pearl = 25D
Source:
http://www.mazdaparts.org/ma5touppa.html
However... in the US at least, Whitewater Pearl was the white color used on '06/'07 models.
The white color on '08/'09 models is "Crystal White Pearl", color code = 34K.
Take a look on the sticker on the inside of your driver's side door - it should give you the exterior color code. I haven't double checked this myself but on other cars I've owned, the color code is on that sticker.
