Being from Australia I've been looking into the possibility of an aussie exchange.
Unfortunately the process of setting up an FX exchange required a licence, which requires 3 years of experience.http://www.holleynethercote.com.au/HN/Financial-Services/Provide-Foreign-Exchange-in-Australia.aspx
And from what I have read there does not appear to be any minimum amount of trading that can be done without a licence.
The other option is to insist it is not currency, but then you will need to deal with GST.
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