hi guys im using ettercap from bt2 from HD, and works really fine until today, maybe... edit some file just for error or im doing something wrong.
using this sintaxis, and not always with the same sintaxis or attack:

ettercap -T -Q -M arp:remote /X.X.X.X/ // -P remote_browser

the ettercap scan the avaible hosts, when its start the attack.. appear some like this:

iptables v1.3.5: can't initialize iptables table `nat': Permission denied (you must be root)
Perhaps iptables or your kernel needs to be upgraded.

i did not re-compile the kernel, nothing like that.