Stickmans Items error

[23:24:41] [Server thread/INFO]: Anikamarie issued server command: /plugman enable stickmans_items
[23:24:41] [Server thread/INFO]: [Stickmans_items] Enabling Stickmans_items v5.4.6
[23:24:41] [Server thread/INFO]: [Stickmans items]Succesfully enabled! By stickman561 and snakec0de companies!
[23:24:47] [Server thread/INFO]: Anikamarie issued server command: /craft
[23:24:56] [Server thread/INFO]: Anikamarie issued server command: /craft
[23:25:52] [Server thread/INFO]: twelveh issued server command: /home storage
[23:26:12] [Server thread/ERROR]: Could not pass event PlayerInteractEvent to Stickmans_items v5.4.6
org.bukkit.event.EventException
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:305) ~[minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at org.bukkit.craftbukkit.v1_8_R1.event.CraftEventFactory.callPlayerInteractEvent(CraftEventFactory.java:226) [minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at org.bukkit.craftbukkit.v1_8_R1.event.CraftEventFactory.callPlayerInteractEvent(CraftEventFactory.java:193) [minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at net.minecraft.server.v1_8_R1.PlayerInteractManager.a(PlayerInteractManager.java:107) [minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at net.minecraft.server.v1_8_R1.PlayerConnection.a(PlayerConnection.java:588) [minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at net.minecraft.server.v1_8_R1.PacketPlayInBlockDig.a(SourceFile:40) [minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at net.minecraft.server.v1_8_R1.PacketPlayInBlockDig.a(SourceFile:10) [minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at net.minecraft.server.v1_8_R1.PacketHandleTask.run(SourceFile:13) [minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) [?:1.7.0_71]
	at java.util.concurrent.FutureTask.run(FutureTask.java:262) [?:1.7.0_71]
	at net.minecraft.server.v1_8_R1.MinecraftServer.z(MinecraftServer.java:683) [minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at net.minecraft.server.v1_8_R1.DedicatedServer.z(DedicatedServer.java:316) [minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at net.minecraft.server.v1_8_R1.MinecraftServer.y(MinecraftServer.java:623) [minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at net.minecraft.server.v1_8_R1.MinecraftServer.run(MinecraftServer.java:526) [minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	at java.lang.Thread.run(Thread.java:745) [?:1.7.0_71]
Caused by: java.lang.NullPointerException
	at com.snakec0de.stickmansitems.StickmansItemsCore.interact(StickmansItemsCore.java:893) ~[?:?]
	at sun.reflect.GeneratedMethodAccessor469.invoke(Unknown Source) ~[?:?]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.7.0_71]
	at java.lang.reflect.Method.invoke(Method.java:606) ~[?:1.7.0_71]
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:301) ~[minecraft_server.jar:git-Spigot-9b45d9f-6b061e2]
	... 17 more