OK I have the following set up on my iPhone:
I setup a couple of apps to allow me to connect to my NAS remotely using a VPN. After that I launch PP, it discovers the NAS and it allows me to stream music remotely over 3G. It works very well for the most part.
I am trying to do the same setup for the Mac OS PP app I just purchased today. I would like to be able to stream my stuff when my I am away from my home wireless network. Again I setup a couple of apps to allow me to connect to the NAS using a VPN. This time though the NAS won't show up under the servers. Here is the kicker though, if I connect to the home wireless network with the NAS and stream music AND then connect to the server using the VPN se up and try to play something, it will play. The issues seems to be that the server won't show up under PP.