networking in virtualbox
 

I virtualised backtrack on windows 7, and set up the network connection to bridged mode, but my networking still fails.
dhclient eth0, outputs many DHCPDISCOVER but no DHCP offers.

have you tried this?

I had a problem like that and discovered that the bridge was looking at the wrong adapter type in Virtual Box settings.

VB had several adapter types listed under Settings-->Network--Advanced-->Adapter Type. The wrong type was selected.

I don't know enough about VB to know why it showed several adapter types, but I do know that making the correct selection got it to connect to the Big Wide World, which was my interest (I haven't progressed to trying to integrate a virtual computer into my local network yet).