I've been getting this error,,

Hello,
I'm trying to set up a new server at the moment but I keep running in this error and I don't know how to fix it. Maybe it's chatmanager but I really don't know how.

This is the error:

Code:

[15:53:51] [Netty IO #1/ERROR]: Could not pass event AsyncPlayerChatEvent to ChatManager v3.0
org.bukkit.event.EventException
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:320) ~[craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:486) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:468) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.server.v1_7_R1.PlayerConnection.chat(PlayerConnection.java:878) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.server.v1_7_R1.PlayerConnection.a(PlayerConnection.java:828) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.server.v1_7_R1.PacketPlayInChat.a(PacketPlayInChat.java:28) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.server.v1_7_R1.PacketPlayInChat.handle(PacketPlayInChat.java:47) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.server.v1_7_R1.NetworkManager.a(NetworkManager.java:72) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.server.v1_7_R1.NetworkManager.channelRead0(NetworkManager.java:192) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:98) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:173) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:173) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:103) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.handler.timeout.ReadTimeoutHandler.channelRead(ReadTimeoutHandler.java:149) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:785) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:100) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:480) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:447) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:341) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at net.minecraft.util.io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:101) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    at java.lang.Thread.run(Unknown Source) [?:1.7.0_51]
Caused by: java.lang.NoClassDefFoundError: net/milkbowl/vault/economy/Economy
    at net.minefactory.chatmanager.ChatListener.onNickChat(ChatListener.java:48) ~[?:?]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.7.0_51]
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.7.0_51]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.7.0_51]
    at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.7.0_51]
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:318) ~[craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
    ... 31 more

I hope someone is able to help me,
Thanks for trying!
- Rick