Task #22 for TheWalls v1.0.3

2013-03-23 08:57:58 [WARNING] [TheWalls] Task #22 for TheWalls v1.0.3 generated an exception
java.lang.NullPointerException
	at rubik_cube_man.plugins.walls.Arena.counter(Arena.java:526)
	at rubik_cube_man.plugins.walls.Walls$1.run(Walls.java:114)
	at org.bukkit.craftbukkit.v1_5_R2.scheduler.CraftTask.run(CraftTask.java:53)
	at org.bukkit.craftbukkit.v1_5_R2.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:344)
	at net.minecraft.server.v1_5_R2.MinecraftServer.r(MinecraftServer.java:512)
	at net.minecraft.server.v1_5_R2.DedicatedServer.r(DedicatedServer.java:225)
	at net.minecraft.server.v1_5_R2.MinecraftServer.q(MinecraftServer.java:476)
	at net.minecraft.server.v1_5_R2.MinecraftServer.run(MinecraftServer.java:409)
	at net.minecraft.server.v1_5_R2.ThreadServerApplication.run(SourceFile:573)