OITC Error

2013-08-23 03:40:02 [SEVERE] Error occurred while enabling OITC v1.7 (Is it up to date?)
java.lang.NullPointerException
	at org.bukkit.Location.getBlock(Location.java:82)
	at com.markyshuk.OITC.Arena.updateSigns(Arena.java:440)
	at com.markyshuk.OITC.Arena.stop(Arena.java:558)
	at com.markyshuk.OITC.OITC.onEnable(OITC.java:85)
	at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:217)
	at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:457)
	at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:382)
	at org.bukkit.craftbukkit.v1_6_R2.CraftServer.loadPlugin(CraftServer.java:286)
	at org.bukkit.craftbukkit.v1_6_R2.CraftServer.enablePlugins(CraftServer.java:268)
	at net.minecraft.server.v1_6_R2.MinecraftServer.l(MinecraftServer.java:319)
	at net.minecraft.server.v1_6_R2.MinecraftServer.f(MinecraftServer.java:296)
	at net.minecraft.server.v1_6_R2.MinecraftServer.a(MinecraftServer.java:256)
	at net.minecraft.server.v1_6_R2.DedicatedServer.init(DedicatedServer.java:164)
	at net.minecraft.server.v1_6_R2.MinecraftServer.run(MinecraftServer.java:397)
	at net.minecraft.server.v1_6_R2.ThreadServerApplication.run(SourceFile:582)