I'm using spring 1.01 hibernate 2.1.2 and mysql. I'm trying to run unit tests on my DAOs(load/saving/deleting) which are going well except for saving "native" id-generated objects. Saving "assigned" id-generated objects works well. 
For the tests i prepopulate the table with data and even supply ids for "natively" created ids.Here is  a sample of sql to populate db.   [librarydemo].
Code:
create table reservations (
   id BIGINT NOT NULL AUTO_INCREMENT,
   book_id VARCHAR(25),
   date_made DATE,
   member_id VARCHAR(20),
   remarks VARCHAR(255),
   limit_in_days INTEGER,
   primary key (id)
);
Code:
insert into reservations values (1,'1-86100-784-1','2004-04-25','2004-1238','1st reserver',25);
insert into reservations values (2,'1-861002-23-8','2004-04-26','2004-1243','1st reserver',25);
The code snippets in java are as follows
Code:
@hibernate.class table="reservations"
public class Reservation
{
    /*
     *    @hibernate.id
     *             name="id" 
     *             type="long"
     *             column="id" 
     *             unsaved-value="-1" 
     *             generator-class="native"
     */
    public Long getId() 
    {
        return this.id;
    }
.  . . .
}