How to get EntityManager from Schedulable?

[nthompson.nate.cimconsultants.com]

Greetings.

I'm trying to implement a nightly job via the org.jboss.varia.scheduler.Scheduler mbean that requires access to the database.  I'm unsure about the correct way to obtain a reference to the database/EntityManager.

If I try

        EntityManagerFactory emf = Persistence 
              .createEntityManagerFactory("my-persistence-unit-name");
        this.em = emf.createEntityManager();

I get errors about there not being a transaction...

What is the correct way to do this?

Thanks,

Nate