Quests console error

[00:00:00] [Server thread/ERROR]: Could not pass event PlayerMoveEvent to Quests v1.8.1
org.bukkit.event.EventException
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:320) ~[craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:486) [craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:471) [craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.PlayerConnection.a(PlayerConnection.java:234) [craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.PacketPlayInFlying.a(SourceFile:137) [craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.PacketPlayInPosition.handle(SourceFile:63) [craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.NetworkManager.a(NetworkManager.java:146) [craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.ServerConnection.c(SourceFile:134) [craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.MinecraftServer.u(MinecraftServer.java:655) [craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.DedicatedServer.u(DedicatedServer.java:250) [craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.MinecraftServer.t(MinecraftServer.java:545) [craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java:457) [craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:617) [craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
Caused by: java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
	at java.util.LinkedList.checkElementIndex(LinkedList.java:553) ~[?:1.7.0_51]
	at java.util.LinkedList.get(LinkedList.java:474) ~[?:1.7.0_51]
	at me.blackvein.quests.Quester.loadData(Quester.java:2467) ~[?:?]
	at me.blackvein.quests.Quests.getQuester(Quests.java:1898) ~[?:?]
	at me.blackvein.quests.PlayerListener.onPlayerMove(PlayerListener.java:667) ~[?:?]
	at sun.reflect.GeneratedMethodAccessor207.invoke(Unknown Source) ~[?:?]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.7.0_51]
	at java.lang.reflect.Method.invoke(Method.java:606) ~[?:1.7.0_51]
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:318) ~[craftbukkit_beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	... 13 more