Minecraft Level 1000 enchant not working?

Alright so basically in minecraft, I used a plugin called Tim the enchanter which in sure most of you mc players have heard of. But after I enchant my leather armor protection 1000, and I go fight against a wave of zombies, it's as if the enchantment wasn't even there! Please help, or explain if there's a way to make the resistance potion effect do less than 20%, since every time I make a res 5+ pot, it seems to make me invincible, but thats not what I want.