Hello, I'm currently trying to create my own silk spawner plugin for my server. But I'm currently running into an issue with the place event. Every time I attempt to place a spawner from my plugin, I get an error each time from EssentialsX v2.0.1-b468.
Error:

[21:46:13 ERROR]: Could not pass event BlockPlaceEvent to Essentials v2.0.1-b468
org.bukkit.event.EventException
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:305) ~[spigot.jar:git-Spigot-c3c767f-33d5de3]
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot.jar:git-Spigot-c3c767f-33d5de3]
at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [spigot.jar:git-Spigot-c3c767f-33d5de3]
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [spigot.jar:git-Spigot-c3c767f-33d5de3]
at org.bukkit.craftbukkit.v1_8_R1.event.CraftEventFactory.callBlockPlaceEvent(CraftEventFactory.java:125) [spigot.jar:git-Spigot-c3c767f-33d5de3]
at net.minecraft.server.v1_8_R1.ItemStack.placeItem(ItemStack.java:154) [spigot.jar:git-Spigot-c3c767f-33d5de3]
at net.minecraft.server.v1_8_R1.PlayerInteractManager.interact(PlayerInteractManager.java:503) [spigot.jar:git-Spigot-c3c767f-33d5de3]
at net.minecraft.server.v1_8_R1.PlayerConnection.a(PlayerConnection.java:724) [spigot.jar:git-Spigot-c3c767f-33d5de3]
at net.minecraft.server.v1_8_R1.PacketPlayInBlockPlace.a(PacketPlayInBlockPlace.java:50) [spigot.jar:git-Spigot-c3c767f-33d5de3]
at net.minecraft.server.v1_8_R1.PacketPlayInBlockPlace.a(PacketPlayInBlockPlace.java:80) [spigot.jar:git-Spigot-c3c767f-33d5de3]
at net.minecraft.server.v1_8_R1.PacketHandleTask.run(SourceFile:13) [spigot.jar:git-Spigot-c3c767f-33d5de3]
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_111]
at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_111]
at net.minecraft.server.v1_8_R1.MinecraftServer.z(MinecraftServer.java:696) [spigot.jar:git-Spigot-c3c767f-33d5de3]
at net.minecraft.server.v1_8_R1.DedicatedServer.z(DedicatedServer.java:316) [spigot.jar:git-Spigot-c3c767f-33d5de3]
at net.minecraft.server.v1_8_R1.MinecraftServer.y(MinecraftServer.java:634) [spigot.jar:git-Spigot-c3c767f-33d5de3]
at net.minecraft.server.v1_8_R1.MinecraftServer.run(MinecraftServer.java:537) [spigot.jar:git-Spigot-c3c767f-33d5de3]
at java.lang.Thread.run(Unknown Source) [?:1.8.0_111]
Caused by: java.lang.IllegalArgumentException
at net.ess3.nms.v1_8_R1.v1_8_R1SpawnerProvider.getEntityType(v1_8_R1SpawnerProvider.java:36) ~[?:?]
at com.earth2me.essentials.EssentialsBlockListener.onBlockPlace(EssentialsBlockListener.java:39) ~[?:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_111]
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_111]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_111]
at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_111]
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:301) ~[spigot.jar:git-Spigot-c3c767f-33d5de3]
... 17 more

If this is still an issue, what version of Spigot are you testing on? /version

In addition, make sure the spawner has the correct NBT tag set, as this is what causes this error.

Closing due to lack of response. If this is still a problem, feel free to reopen the issue.