Why can't I open ports for my p2p applications?

[Schulz]

I'm using leopard for the past two days, anything is working fine AFAIK, but I can't seem open a port for Transmission for example.At the router firewall, I've set up a bimap rule to forward all ports as in windows, so I think it's ok with it, but leopard keep saying my ports are closed.I've already played with firewall configs at leopard, but it doesn't seem to be blocking anything...My ethernet card is Marvell Yukon, onboard on my p5b deluxe moherbard.What i've noticed is that my ethernet MAC address is different at leopard. But I don't know if this can mess up the forwarding in my modem.Any help is welcome, tanksNevermind, I've solved the problem myself, router misconfiguration...thanks anyway