In my code a session bean(Bean Managed Txn) buisiness method is updating An Entity(CMP) Bean. I am using UserTransaction in session bean. The problem is that session bean method is updating many rows of a Table (in for loop) After the for loop completes then i am commiting the txn by txn.comit(); If i get any exception i will do roll back. But it is not working properly. The transaction is never rolled back. Please give me a idea.