* Is Tx open? ODMG 3.0 says it has to be to call unbind.
*/
TransactionImpl tx = getTransaction();
if (tx == null || !tx.isOpen())
{
throw new TransactionNotInProgressException("Tx is not open. Must have an open TX to call unbind.");
}
boolean failedPersistent = false;
boolean failedCurrentTx = false;
// to make nrm entries visible during running transactions, transactions maintain