I already have sancho configured in that way but it doesn't work.
After some time (ip change) I get lowid in the edonkey servers and the ports are not open.
What connection do you have, ADSL or CABLE?
I.e. I have cable, and my IP stays the same until I turn on/off my cable modem (and sometimes even if I do that, it remains the same)...
I've a DSL connection and my ISP (do me (not) the favor of) change the IP during the connection some times even during the connection up time.
So, I've to continually do the iptables "trick".