treeassist error

2013-05-14 14:40:45 [SEVERE] Could not pass event BlockPlaceEvent to TreeAssist v5.4.3
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 org.bukkit.craftbukkit.v1_5_R3.event.CraftEventFactory.callBlockPlaceEvent(CraftEventFactory.java:108)
    at net.minecraft.server.v1_5_R3.ItemBlock.processBlockPlace(ItemBlock.java:85)
    at net.minecraft.server.v1_5_R3.ItemBlock.interactWith(ItemBlock.java:71)
    at net.minecraft.server.v1_5_R3.ItemStack.placeItem(ItemStack.java:79)
    at net.minecraft.server.v1_5_R3.PlayerInteractManager.interact(PlayerInteractManager.java:386)
    at net.minecraft.server.v1_5_R3.PlayerConnection.a(PlayerConnection.java:631)
    at net.minecraft.server.v1_5_R3.Packet15Place.handle(SourceFile:58)
    at net.minecraft.server.v1_5_R3.NetworkManager.b(NetworkManager.java:292)
    at net.minecraft.server.v1_5_R3.PlayerConnection.d(PlayerConnection.java:109)
    at net.minecraft.server.v1_5_R3.ServerConnection.b(SourceFile:35)
    at net.minecraft.server.v1_5_R3.DedicatedServerConnection.b(SourceFile:30)
    at net.minecraft.server.v1_5_R3.MinecraftServer.r(MinecraftServer.java:581)
    at net.minecraft.server.v1_5_R3.DedicatedServer.r(DedicatedServer.java:226)
    at net.minecraft.server.v1_5_R3.MinecraftServer.q(MinecraftServer.java:477)
    at net.minecraft.server.v1_5_R3.MinecraftServer.run(MinecraftServer.java:410)
    at net.minecraft.server.v1_5_R3.ThreadServerApplication.run(SourceFile:573)
Caused by: java.lang.NullPointerException
    at me.itsatacoshop247.TreeAssist.TreeAssistBlockListener.onBlockPlace(TreeAssistBlockListener.java:217)
    at sun.reflect.GeneratedMethodAccessor172.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)
    ... 19 more

http://dev.bukkit.org/server-mods/tree-assist/tickets/141-not-working-on-1-5-2/