NBT hacks?

I am an administrator on a fairly large Minecraft server and lately more and more hacked items have been popping up. Things like armor and swords usually are appearing with enchantment levels typically of 1000 with the top being 32767. Me and the other admins have been trying frantically to figure out how players are accomplishing this, as more have been showing up every day. I know about certain clients like Kinky and Weepcraft that offer NBT hacks for players with creative mode. But they have caps on them. Does anyone know of a client maybe that lets the hacked items get specific enchants and edit other nbt values as well. It may not be a client, it could be a mod. We don't have Tim the Enchanter plugin or any server side mods that would enable this as far as we know. Other hacked nbt values include potions with crazy values and playerheads with specific players. Any help appreciated!

clients couldnt do that, i think the items are server handled. There might either be an admin, or maybe something via cheat engine.. i dont know much about cheat engine but it lets people to edit values at certain addresses.. In which case, it would be for the specified item and its enchantment level..