Crash

7:06:40 [INFO] Sxw1212[/127.0.0.1:59527] logged in with entity id 245032 at ([world] 9.366645138843106, 65.0, 1.8879449595078142)
17:06:40 [SEVERE] java.lang.ArrayIndexOutOfBoundsException: -1
17:06:40 [SEVERE]   at java.util.ArrayList.get(ArrayList.java:324)
17:06:40 [SEVERE]   at net.minecraft.server.management.ServerConfigurationManager.func_72374_b(ServerConfigurationManager.java:1125)
17:06:40 [SEVERE]   at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:918)
17:06:40 [SEVERE]   at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:330)
17:06:40 [SEVERE]   at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:781)
17:06:40 [SEVERE]   at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:663)
17:06:40 [SEVERE]   at net.minecraft.server.ThreadMinecraftServer.run(ThreadMinecraftServer.java:16)
17:06:40 [SEVERE] Encountered an unexpected exception ArrayIndexOutOfBoundsException
java.lang.ArrayIndexOutOfBoundsException: -1
    at java.util.ArrayList.get(ArrayList.java:324)
    at net.minecraft.server.management.ServerConfigurationManager.func_72374_b(ServerConfigurationManager.java:1125)
    at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:918)
    at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:330)
    at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:781)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:663)
    at net.minecraft.server.ThreadMinecraftServer.run(ThreadMinecraftServer.java:16)
17:06:40 [SEVERE] This crash report has been saved to: /Users/sam/IrresponsibleCraft/./crash-reports/crash-2014-06-22_17.06.40-server.txt