Connection con = pb.serviceConnectionManager().getConnection();
Integer previousIsolationLevel = DataSourceUtils.prepareConnectionForTransaction(con, definition);
txObject.setPreviousIsolationLevel(previousIsolationLevel);
pb.beginTransaction();
// Register the OJB PersistenceBroker's JDBC Connection for the DataSource, if set.
if (getDataSource() != null) {
ConnectionHolder conHolder = new ConnectionHolder(con);
if (definition.getTimeout() != TransactionDefinition.TIMEOUT_DEFAULT) {