Bukkit

What steps will reproduce the problem?
1.Restarting the Server after creating any arenas..
2.
3.

What is the expected output? What do you see instead?

After setting up an Arena, I restart the server. In the game, Plugin Slash-Commands no longer show any output. No error, no information at all. LobbySigns show the status 'stopped', but you can't right-click to join. Nothing works at all.
If arena.yml is empty or missing, the plugin operates perfectly after a restart. You can set up multiple Arenas that work perfectly. Until you restart the server again.

What version of the product are you using?

HungerGames 2.2
Spigot 1.7.2

Do you have an error log of what happened?

No, unfortunately there is no output.

Please provide any additional information below.

I disabled every other plugin on my server and the issue persisted.