Unfortunately I have never used mono so I don't know how that would work.
As for other queue implementations: I have implemented only a sql table-based queue and the msmq implementation but Shuttle can work with
any queue implementation. There is an IQueue
interface and the corresponding IQueueFactory interface in Shuttle.ESB.Core that you would need to implement. You could have a look at the code of the msmq implementation as an example.
It would be first prize if we could add your code to Shuttle :)