Write test to test rollback of a NACK in 2PC

Need to test BasicQueue.acknowledge()
whether it should also add a PostRollback task for a NACK under a transaction.

i.e.

// Was it a negative acknowledge??
if (!item.isAck)

{ Runnable task = new RestoreMessageTask(m); server.getPersistenceManager().getTxManager().addPostCommitTask(txId, task); + server.getPersistenceManager().getTxManager().addPostRollbackjTask(txId, task); }

The hard part is wrting such a test since it is a normal condition.
Probably need to use direct invocation on the server invoker ?