MAC address weirdness on eth0

Hi all,

i've just purchased an openbrick and loaded Leaf Bering 1.2 on it, this 
is amazing ....
however i've got a small problem with the embedded ehternet interface : 
when the interface is up, it always has a mac address of 
ff:ff:ff:ff:ff:ff. Of course, it causes a lot of problems. What i've 
done so far is assign an address of my invention before the interface is 
brought up but this is just a temporary hack and cannot be considered as 
a "good" solution.
I would like to know if anyone has seen this before and if there's a 
special trick to get the real network card mac address instead of 
getting the broadcast address assigned to the card.
The card is a realteck and i'm using the 8139too and mii drivers.
Here are the messages logged at boot time :

8139too Fast Ethernet driver 0.9.26                                        
PCI: Assigned IRQ 10 for device 00:0e.0                                    
eth0: RealTek RTL8129 at 0xc8833000, ff:ff:ff:ff:ff:ff, IRQ 10             
eth0: No MII transceivers found!  Assuming SYM transceiver.        
eth0: Setting half-duplex based on auto-negotiated partner ability 0000

Any help would be appreciated.
Thanks
Charles-Edouard Ruault