This is a mess. I am half way through making up some patches to fix it properly. (literally I have a window at work with the half-editted sources on it :)

htons will correctly smash up the lower 16 bits of a long under a little-endian OS. so using htons, while being totoally un-portable will probably work, but htonl will do the correct thing, and the lower 16 bits of the port will become 0. The correct answer is to change teh port numbers where-ever they are in natd to be unsigned short. I am doing this.. I'll add the changes in a few days.