[ubuntu] Help with configuration of Virtualbox bridged mode

Hi,

I currently am running Ubuntu 12.10 server and I have install Virtualbox Headless. Within Virtualbox, I am running Centos as a guest OS. I'm finding that if I run in Nat mode, I am able to connect out to the internet, but I actually need to run in bridged mode as I need my internal network to be able to access the guest. I am able to ping the guest from the host and ping the host from the guest in bridged mode, but I am not able to ping anything beyond the host. I am wondering if I am missing something and some help would be very much appreciated.

Anthony