(cut out earlier summary about bridging not coming up). What is happening? My guess is that the network device is not reporting carrier present so the bridge thinks the link is down. You can check for carrier status by looking at /sys/class/net/eth0/carrier and/or 'brctl showstp br0' will show eth0 as disabled. If this is the case, it is a network driver problem, what is the network device? It is probably fixable with a simple patch to that driver.
