Her profile on Naver says she was born in 1982, but some people put up her high school graduation pictures which say that she went to Cerritos High School and her graduation year was 1998.  That would mean she was born in 1980, not 1982.

Her agency claims that when she began her career she stated her age as the international age, and when she started to do work in Korea the international and Korean age got mixed up.  It seems like the problem arose becuase of the different ways in which Korea and the rest of the world count age.

At any rate, the agency says her real birth year was 1981.

Han Ye-seul