Zune Pass is going to open up in Australia but it seems according to some forum members at XDA it still not availble for everybody. The Music + Video thing is still missing in Zune so if you want to get it activated it like right now, Chris Walsh has written which lets you do that and also it enables lot of hidden features like Podcast Marketplace
He has used a tool called as Fidler which is a Web Debugging Proxy to can see the traffic between your computer and the internet. So basically you can find any request even if it is not from a browser but done from an application.
Now What Walsh has done here is use Auto Responder which allows you to return files from your local disk instead of transmitting the request to the server. So When Zune Requests for a configuration file from server, Fiddler returns the response with a config file from your local hard disk which has been set to enable Zune Pass for you.
Chris as recommended to clean up your browser cookies, cache and settings also. Now before you start trying out for yourself this trick is working for only Australia because you need the right config file with right settings to return. So unless you get to understand what is in the config file you wont be able to enable Zune Pass for your country.