Table with two primary keys(hibernate persistence)

Hello..

I am currently working on a program. Im using hibernate as persistence.
Problem: I have a table in my database w/c has two primary keys, when the pojo was generated, the ID was put in a separate class. when I try to create a code that would persist data in that table with two primary keys, i could not find any way. I dont know how to deal with it because its my first time to encounter a table with two primary keys. Can anyone help me or give me a site that conduct a tutorial in dealing table with two primary keys using hibernate as persistence.

PS: I am using SQLYOG as my database.
I am using java.

Thanks a lot.