[MultiKill] Task #47 for MultiKill v0.2 generated an exception
java.util.ConcurrentModificationException
	at java.util.HashMap$HashIterator.nextEntry(HashMap.java:926) ~[?:1.7.0_51]
	at java.util.HashMap$KeyIterator.next(HashMap.java:960) ~[?:1.7.0_51]
	at de.marcmaurer.pentakill.MAIN$1.run(MAIN.java:43) ~[?:?]
	at org.bukkit.craftbukkit.v1_7_R3.scheduler.CraftTask.run(CraftTask.java:53) ~[craftbukkit.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at org.bukkit.craftbukkit.v1_7_R3.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:345) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.MinecraftServer.v(MinecraftServer.java:600) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.DedicatedServer.v(DedicatedServer.java:260) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.MinecraftServer.u(MinecraftServer.java:558) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.MinecraftServer.run(MinecraftServer.java:469) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.ThreadServerApplication.run(SourceFile:628) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]