Go to custom player and enter any of the following names 
to unlock that character. Press DONE two times to activate. 

Code            Result 
----------------------
BARRY DEJAY   - Barry Dejay 
LEMON BOY     - Thor Herring 
KOBE          - Kobe Bryant 
SHAQ          - Shaquille O'Neal 
VINCE         - Vince Carter 
MJ            - Michael Jordan 
ALLEN IVERSON - Allen Iverson