Minecraft 1.6.2 dupe glitch mcMMO HD

Working dupe glitch in Minecraft 1.6.2 with mcMMO power ups. Works in multiplayer. Infinite experience. How to do this glitch: Have only a stack and one ore of diamond in your inventory. Put in hotbar to see better. Right click the dirt block, throw the stack of ore, then break the dirt block. Do not move. You should pick up a full stack of diamond ore, and now have two stacks of diamond ore.