When you break a PS this happens even with latest dev from Dec. 19

2012-12-20 23:14:43 [SEVERE] Could not pass event BlockBreakEvent to PreciousStones v9.5.4-SNAPSHOT
org.bukkit.event.EventException
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:427)
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:477)
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:462)
at net.minecraft.server.v1_4_6.PlayerInteractManager.breakBlock(PlayerInteractManager.java:282)
at net.minecraft.server.v1_4_6.PlayerInteractManager.a(PlayerInteractManager.java:209)
at net.minecraft.server.v1_4_6.PlayerConnection.a(PlayerConnection.java:567)
at net.minecraft.server.v1_4_6.Packet14BlockDig.handle(SourceFile:46)
at net.minecraft.server.v1_4_6.NetworkManager.b(NetworkManager.java:290)
at net.minecraft.server.v1_4_6.PlayerConnection.d(PlayerConnection.java:112)
at net.minecraft.server.v1_4_6.ServerConnection.b(SourceFile:39)
at net.minecraft.server.v1_4_6.DedicatedServerConnection.b(SourceFile:30)
at net.minecraft.server.v1_4_6.MinecraftServer.r(MinecraftServer.java:598)
at net.minecraft.server.v1_4_6.DedicatedServer.r(DedicatedServer.java:224)
at net.minecraft.server.v1_4_6.MinecraftServer.q(MinecraftServer.java:494)
at net.minecraft.server.v1_4_6.MinecraftServer.run(MinecraftServer.java:427)
at net.minecraft.server.v1_4_6.ThreadServerApplication.run(SourceFile:849)
Caused by: java.util.ConcurrentModificationException
at java.util.HashMap$HashIterator.nextEntry(Unknown Source)
at java.util.HashMap$KeyIterator.next(Unknown Source)
at net.sacredlabyrinth.Phaed.PreciousStones.managers.EntryManager.removeAllPlayers(EntryManager.java:627)
at net.sacredlabyrinth.Phaed.PreciousStones.managers.ForceFieldManager.deleteField(ForceFieldManager.java:459)
at net.sacredlabyrinth.Phaed.PreciousStones.managers.ForceFieldManager.releaseNoDrop(ForceFieldManager.java:2265)
at net.sacredlabyrinth.Phaed.PreciousStones.listeners.PSBlockListener.removeAndRefundBlock(PSBlockListener.java:625)
at net.sacredlabyrinth.Phaed.PreciousStones.listeners.PSBlockListener.breakingFieldChecks(PSBlockListener.java:596)
at net.sacredlabyrinth.Phaed.PreciousStones.listeners.PSBlockListener.handleBreak(PSBlockListener.java:403)
at net.sacredlabyrinth.Phaed.PreciousStones.listeners.PSBlockListener.onBlockBreak(PSBlockListener.java:326)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:425)
... 16 more

Duplicate of #505