Am Mittwoch, den 28.03.2007, 13:30 -0700 schrieb Patrick Linskey:
Are you ever sharing EMs across multiple sequential JTA transactions?

As far as I can say: definitely NO. But the EMF used to create the EM's is held as a static member of a Helper Class.
I.e. 2 different threads accessing the EMF to create the EM in parallel could be the cause of the problem?