No worries, Vaskez. You could also have been talking about me, 'cause I've done this a few times, but never before on XP. So to some extent, I have the theoretical knowledge there, but not the practical knowledge. It is apparent, though, that you have far more in-depth technical knowledge than I do
And Philip, I know it's not secure. Locks are only there to keep honest people honest, so by putting more hurdles in the way, I make it harder to get in, and any would-be hacker would simply go to my neighbor's house, since he doesn't know about changing any of the defaults. I'm also restricting based on MAC address, but that's not foolproof either; all I have to do is spoof that address, and if everything else is lined up, I can get in.
After I got my brother convinced that wireless was okay, he came across an article where a journalist had decided to see just what he had to do to break into a shielded wireless network (hidden, restricted MAC, 128-bit WEP). Took him about five hours, including downloading the necessary tools...
Seems to me that it might be something related to connecting to unpreferred networks, but since the critter is now working upstairs, I'm going to leave it alone for now. I broke enough other things last night...