server crash

---- Minecraft Crash Report ----

WARNING: coremods are present:
  SpongeCoremod (sponge-1.8-1499-2.1DEV-615.jar)
Contact their authors BEFORE contacting forge

// I'm sorry, Dave.

Time: 9/22/15 11:58 AM
Description: Exception in server tick loop

java.lang.NoClassDefFoundError: org/spongepowered/api/event/message/MessageEvent
	at java.lang.Class.forName0(Native Method)
	at java.lang.Class.forName(Class.java:348)
	at org.spongepowered.mod.plugin.SpongeModPluginContainer.constructMod(SpongeModPluginContainer.java:98)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:497)
	at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74)
	at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47)
	at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322)
	at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304)
	at com.google.common.eventbus.EventBus.post(EventBus.java:275)
	at net.minecraftforge.fml.common.LoadController.sendEventToModContainer(LoadController.java:212)
	at net.minecraftforge.fml.common.LoadController.propogateStateMessage(LoadController.java:190)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:497)
	at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74)
	at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47)
	at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322)
	at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304)
	at com.google.common.eventbus.EventBus.post(EventBus.java:275)
	at net.minecraftforge.fml.common.LoadController.distributeStateMessage(LoadController.java:119)
	at net.minecraftforge.fml.common.Loader.loadMods(Loader.java:507)
	at net.minecraftforge.fml.server.FMLServerHandler.beginServerLoading(FMLServerHandler.java:87)
	at net.minecraftforge.fml.common.FMLCommonHandler.onServerStart(FMLCommonHandler.java:355)
	at net.minecraft.server.dedicated.DedicatedServer.func_71197_b(DedicatedServer.java:117)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:438)
	at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.ClassNotFoundException: org.spongepowered.api.event.message.MessageEvent
	at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:191)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
	... 30 more
Caused by: java.lang.NullPointerException
	at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:182)
	... 32 more


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- System Details --
Details:
	Minecraft Version: 1.8
	Operating System: Linux (amd64) version 3.14.32-xxxx-std-ipv6-64-hz1000
	Java Version: 1.8.0_60, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 345095480 bytes (329 MB) / 518979584 bytes (494 MB) up to 2075918336 bytes (1979 MB)
	JVM Flags: 21 total; -Xincgc -XX:+UseParNewGC -XX:MaxPermSize=256M -XX:NewRatio=2 -XX:CMSFullGCsBeforeCompaction=1 -XX:+UseConcMarkSweepGC -XX:SoftRefLRUPolicyMSPerMB=2048 -XX:+CMSParallelRemarkEnabled -XX:+UseAdaptiveSizePolicy -XX:+DisableExplicitGC -Xnoclassgc -Xoss4M -Xss4M -XX:+UseFastAccessorMethods -XX:CMSInitiatingOccupancyFraction=90 -XX:UseSSE=4 -XX:+UseCMSCompactAtFullCollection -XX:ParallelGCThreads=4 -XX:+AggressiveOpts -Xmx2048M -Xms512M
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	FML: MCP v9.10 FML v8.0.99.99 Minecraft Forge 11.14.3.1499 6 mods loaded, 6 mods active
	States: 'U' = Unloaded 'L' = Loaded 'C' = Constructed 'H' = Pre-initialized 'I' = Initialized 'J' = Post-initialized 'A' = Available 'D' = Disabled 'E' = Errored
	UC	mcp{9.05} [Minecraft Coder Pack] (minecraft.jar)
	UC	FML{8.0.99.99} [Forge Mod Loader] (sponge-forge-1.8-1499-2.1DEV-615.jar)
	UC	Forge{11.14.3.1499} [Minecraft Forge] (sponge-forge-1.8-1499-2.1DEV-615.jar)
	UC	Sponge{1.8-1499-2.1DEV-615} [SpongeForge] (minecraft.jar)
	U	featherchat{1.1} [FeatherChat] (featherchat-1.1.jar)
	U	PermissionsEx{2.0-SNAPSHOT} [PermissionsEx] (PermissionsEx-Sponge.jar)
	Loaded coremods (and transformers):
SpongeCoremod (sponge-1.8-1499-2.1DEV-615.jar)

	Profiler Position: N/A (disabled)
	Is Modded: Definitely; Server brand changed to 'fml,forge'
	Type: Dedicated Server (map_server.txt)