I have a SessionBean that uses EJB Timer Service, when I started its development the timer was working fine. Suddenly it stopped working complaining that it was unable to persist timer. It took me one day to figure out (I even had to check sources) that it was failing due to (what to me looks like) a problem in transaction management. Is it normal that the createTimer fails when I have a PersistenceContext that is backed up by a Local-TX DataSource in JBoss default configuration? If so, shouldn't it warn or something like? After I changed the Postgres DataSource to XA the timer is working fine. If necessary I can post some sample classes.