Bukkit

What steps will reproduce the problem?
1. load up plugin in ftb modded server
2. ban air
3. players can still use air

What is the expected output? What do you see instead?
expected players not to be able to break blocks (replace with air) didn't work, players remain unaffected.

What version of the product are you using?
newest one as of 4/11/13

Do you have an error log of what happened?
there is not error log generated

Please provide any additional information below.
I added item id's to config, and it deleted it all when i restart my server. I add them ingame and it just wont ban items. period. players remain unaffected.