Put the summary of the bug you're having here
i went into mcedit an ran one of sethblings filters(it made whatever was in the chest have certin atributes like speed or strength) the one that i was making was regen 200%.

What I expected to happen was...:
i would regenerate when holding it(it was paper named in an anvil"scroll of heath").

What actually happened was...:
when i pun my cursor over it minecraft crashed i tried again and i crashed again.

Steps to Reproduce:
1.name a pice of paper"scroll of heath"
2.put it in a chest and go into mcedit ang run the filter select 200 and show presentage
3.go back in to minecraft (in the minecraft lancher for latest version)an put your curser over it. It should crash right there.