The dlna feature in pr 1.2 adds dlna server to n9. You cant push media to dlna devices with it. Only thing we can do is acces stored media from the phone and play it.
Jalyst. I have posted a comment in the blog you mentioned and asked Jens to take a look at this thread
remember you want to stream sound from a mobile phone. if you want to 'push' DLNA streaming it is the source device that is responsible for producing the sound, not the receiving device,