Did you get this going? I'm half asleep, hope this isn't a post from 2 years ago or something.
Until one of the Guru's gets back with you, I can at least point you at this following link;
I've had a few broadcom chips over the years and got them all working by following the info from that site.
They will want you to add some options to the lspci command so it outputs the PCI-ID, and you will compare that PCI-ID to the list to make sure your version of the BCM4318 is supported by them.
Hope this helps,