[arch-general] problem while bridging network

hi listmate, I'm posting 'cause I have some problem when I bridge a connexion. I wanna set up a virtual machine with windws 7 to play eve online (no support for linux at this time, and I can't make it run on wine). So I've follow the wiki for setting up network with the virtual machine. But now, I'm starting my computer with eth0 and vbox0 bridged, but I can't use my wifi connexion on wlan0. If I delete the bridge with a «brctl delbr br0», I can connect to the wifi through wlan0, but my VM haven't any network. To be exact, I can connect me to my personnal network, but this have no internet connexion. Weird. If any one might help me with this, it would be nice. -ludovic