I'm using Hibernate 3.3.1 with Postgres.

My persistence.xml contains the following:
<property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect"/>
<property name="hibernate.connection.driver_class" value="org.postgresql.Driver"/>

I have
@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
private Long id;

@Column(...)
private String name;

I see the db created the column as bigserial, which is what I want.

When I go to persist the object it throws an error saying that the id parameter is blank. Am I missing something here?

org.postgresql.util.PSQLException: No value specified for parameter 2.

Hibernate:
insert
into
users
(name, id)
values
(?, ?)

Also, why would one not want to use IDENTITY when the database supports it?