I'm trying to set up Xen to run on Ubuntu Fiesty. It's booting fine, but now my networking doesn't work at all. Some googling revealed that it's my ethernet card, which is a Broadcom 4401.

So I've downloaded the driver from the Broadcom website, and now I'm installing it using their instructions, and I get an error that says "/lib/modules/2.6.19-4-server/build: no such file or directory"

I've installed both the xen headers and build-essential

Any help would be much appreciated!