As im sure you all know this game is filled with modders and hackers. I was wondering if it was possible to make a plugin that compares the clients minecraft.jar with a clean minecraft.jar to make sure this person has no mods installed.
If this is possible, I would be happy with this. However, I like to have mod from the zombie pack, for the chat bar. So if you could give exceptions somehow that would be great.
Pretty sure this isn't possible. Plus, any firewall worth its salt would be able to stop the checking of the jar easily.