The PSN content now appears to be hosted by Akamai. They are a content provider with servers all over the world. They are used by Microsoft to deliver Windows Updates for example.
Previously when you had a US account, and downloaded something it would come from the server in the US.
Now they use a technology called DNS to direct you to a local server where the content is hosted, meaning it only gets transmitted from the US to Australia (for example) once, and everyone in Australia gets it quicker and more reliablly locally.
Unfortuantely if the content is not yet mirrored locally, (not yet on the Australian Store) it seems you cant download it using the American Store.
I used the Proxy setting in the PS3 Network Settings to use an American Proxy.
This means my PS3 asks an American server to get the file on it's behalf. The American Server then talks to the American Akamai Server which has the content, so I was able to download it.
I hope this makes sense...
Long story short, some content may not be available any more, even if you have accounts in different countries... the work around is to use a proxy in that country.
