So I am currently running a plugin called "Custom Enchantments" on my server. It adds things like poison and other stuff, when I use them they work fine, but when a normal player uses them they do not work. I am not sure if it is a permission that the players or lacking or there is something wrong. Some help with this would be great! Thanks! Plugin link: http://dev.bukkit.org/bukkit-plugins/custom-enchantments/?page=31
If you're OPed on the server, then it's probably the players not having the permission. If you post your permissions here, using pastebin, I'm sure that would help.
