I am trying to insert an object mapped to a table. The table has some foreign keys.

For example

Table USER {
name char(20),
age int,
address varchar(500),
job_id int,
Foreign key job_id references someothertable.field
);

now when I want to create a new user, i may want to create a new job along with it. So in the USER object I fill in the required details of the user and the new job to be created. Saving this object should create a newuser, and the new job. How do I do that ?

I guess you must add cascade="save-update" to your many-to-one in User class mapping.
(I hope I guessed the names, otherwise change them)
However, I usually avoid these situations as I feel I'm loosing control of persisted objects.

Bye
Stefano