// further commands after one fails
TransactionManager mgr = (TransactionManager)ctx.lookup(TransactionManagerService.JNDI_NAME);
DataSource ds = (DataSource)ctx.lookup("java:/DefaultDS");
javax.transaction.Transaction txOld = mgr.suspend();
executeStatement(mgr, ds, "DROP TABLE JBM_POSTOFFICE");
executeStatement(mgr, ds, "DROP TABLE JBM_MSG_REF");