DroolsSpringTransactionManager:

public void begin() {
if ( getStatus() == TransactionManager.STATUS_NO_TRANSACTION )

{ <<<<< IF Spring TX ALREADY EXISTS, "currentTransaction" NEVER GETS INITIALIZED ( GET A REFERENCE TO THE REAL TX ) // If there is no transaction then start one, we will commit within the same Command // it seems in spring calling getTransaction is enough to begin a new transaction currentTransaction = this.ptm.getTransaction( td ); localTransaction = true; }

else

{ localTransaction = false; }

}

So in case "DroolsSpringTransactionManager" decides to, for example, rollback:

public void rollback()

{ this.localTransaction = false; this.ptm.rollback( currentTransaction ); <<< IT'LL THROW A NULLPOINTEREXCEPTION HERE }