Prism Exception reoccuring in the console. running legacy 652

[ProsperCraft]

09:51:53 [WARNING] [Prism] Task #14236 for Prism v2.0Beta2-MCPC-MC1.5-3-gdf5767f-SNAPSHOT generated an exception
java.lang.NullPointerException
at org.bukkit.craftbukkit.v1_5_R3.CraftWorld.getUID(CraftWorld.java:539)
at org.bukkit.craftbukkit.v1_5_R3.CraftWorld.hashCode(CraftWorld.java:1194)
at org.bukkit.Location.hashCode(Location.java:450)
at java.util.concurrent.ConcurrentHashMap.hash(ConcurrentHashMap.java:333)
at java.util.concurrent.ConcurrentHashMap.remove(ConcurrentHashMap.java:1175)
at me.botsko.prism.Prism$4.run(Prism.java:939)
at org.bukkit.craftbukkit.v1_5_R3.scheduler.CraftTask.run(CraftTask.java:58)
at org.bukkit.craftbukkit.v1_5_R3.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:344)
at net.minecraft.server.MinecraftServer.spigotTLETick(MinecraftServer.java)
at net.minecraft.server.MinecraftServer.runQueuedTasks_net_minecraft_server_MinecraftServer_runQueuedTasks_p0(MinecraftServer.java:441)
at net.minecraft.server.MinecraftServer.runQueuedTasks(MinecraftServer.java)
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:371)
at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:320)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:307)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:199)
at net.minecraft.server.ThreadMinecraftServer.run(SourceFile:573)