auto update age with xthreads?

[r0ck]

Hello I own an adult movie review site and I used xthreads to list "models" right now I have date of birth and next to it I would like to add I am X amount years old!  How would I allow this field to auto update every year?  Is it possible?

Like:
Birth Date: February 2nd, 1981  (33 Years Old!)

or better yet:
Birth Date: February 2nd, 1981
Age: 33