James,
Thank you very much for your answer.. 
In this case, I will modify the webgui in order to be able to bridge
LAN and WAN together.
If you think this solution could be interesting for m0n0wall project,
I will send it when it will be finished...
Best regards

Tom
 
> I don't think you can bridge the LAN to the WAN. You can only bridge
> an OPT interface to another interface (LAN, WAN, or other OPT). You
> would need to add a 3rd NIC, bridge to WAN, and set firewall rules to
> meet your needs.
> 
> If you only want to use the bridged network, then the LAN interface
> would become a "Management" interface/network... and for all practical
> purposes the OPT interface would be your "LAN" (although it wild be
> labeled "OPT" or what ever you renamed it - I don't think you can
> rename the "LAN")...