at org.bukkit.craftbukkit.v1_7_R1.scheduler.CraftTask.run(CraftTask.java:53) ~[craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at org.bukkit.craftbukkit.v1_7_R1.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:345) [craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at net.minecraft.server.v1_7_R1.MinecraftServer.u(MinecraftServer.java:587) [craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at net.minecraft.server.v1_7_R1.DedicatedServer.u(DedicatedServer.java:250) [craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at net.minecraft.server.v1_7_R1.MinecraftServer.t(MinecraftServer.java:545) [craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java:457) [craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:617) [craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.v1_6_R3.Packet
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:67) ~[craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:62) ~[craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at java.lang.ClassLoader.loadClass(ClassLoader.java:425) ~[?:1.7.0_55]
        at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ~[?:1.7.0_55]
        ... 9 more
[20:47:14 WARN]: [Quests] Task #11 for Quests v1.7.0 generated an exception
java.lang.NoClassDefFoundError: net/minecraft/server/v1_6_R3/Packet
        at me.blackvein.quests.NpcEffectThread.showEffect(NpcEffectThread.java:93) ~[?:?]
        at me.blackvein.quests.NpcEffectThread.run(NpcEffectThread.java:34) ~[?:?]
        at org.bukkit.craftbukkit.v1_7_R1.scheduler.CraftTask.run(CraftTask.java:53) ~[craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at org.bukkit.craftbukkit.v1_7_R1.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:345) [craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at net.minecraft.server.v1_7_R1.MinecraftServer.u(MinecraftServer.java:587) [craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at net.minecraft.server.v1_7_R1.DedicatedServer.u(DedicatedServer.java:250) [craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at net.minecraft.server.v1_7_R1.MinecraftServer.t(MinecraftServer.java:545) [craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java:457) [craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:617) [craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.v1_6_R3.Packet
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:67) ~[craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:62) ~[craftbukkit-beta.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
        at java.lang.ClassLoader.loadClass(ClassLoader.java:425) ~[?:1.7.0_55]
        at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ~[?:1.7.0_55]
        ... 9 more