Xbox not finding my Pi

I've just received my Pi and got it up and running Raspbmc, but when I try to access it through my Xbox, it doesn't seem to want to find it.
I've been running XBMC since Dharma and have had no problems streaming from my windows computer and I find it odd that it's not working from my Pi.

If anyone has any solutions to this I'd love to hear it so I can get everything working!

Thanks,

Makx