Crash serveur forge 1.8

[Soutekh]

Bonjour,
Je souhaite installer RPCraft Toolkit sur mon serveur (héberger sur mon PC), Forge est déja installer sur le serveur.
J'ai donc mis le mod dans le dossier mods du serveur et là le serveur crash, avant de vouloir installer le mod sur le serveur multi on a essayer de l'utiliser mais les objet que l'on fabriquer disparaisse immédiatement de l'inventaire.
PS: J'ai déjà installer le mod et Forge sur mon Pc et celui de ma sœur sans problème en solo.

---- Minecraft Crash Report ----
// Ooh. Shiny.
 
Time: 30/05/15 16:21
Description: Exception in server tick loop
 
net.minecraftforge.fml.common.LoaderException: java.lang.NoSuchMethodError: net.minecraft.item.ItemStack.func_179549_c(Lnet/minecraft/item/ItemStack;)Z
        at net.minecraftforge.fml.common.LoadController.transition(LoadController.java:163)
        at net.minecraftforge.fml.common.Loader.preinitializeMods(Loader.java:529)
        at net.minecraftforge.fml.server.FMLServerHandler.beginServerLoading(FMLServerHandler.java:88)
        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(Unknown Source)
Caused by: java.lang.NoSuchMethodError: net.minecraft.item.ItemStack.func_179549_c(Lnet/minecraft/item/ItemStack;)Z
        at net.rpcraft.rpcraft.RPCraft.preinit(RPCraft.java:498)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
        at java.lang.reflect.Method.invoke(Unknown Source)
        at net.minecraftforge.fml.common.FMLModContainer.handleModStateEvent(FMLModContainer.java:537)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
        at java.lang.reflect.Method.invoke(Unknown Source)
        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(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
        at java.lang.reflect.Method.invoke(Unknown Source)
        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.preinitializeMods(Loader.java:527)
        ... 5 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: Windows 7 (x86) version 6.1
        Java Version: 1.8.0_45, Oracle Corporation
        Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
        Memory: 75883984 bytes (72 MB) / 153509888 bytes (146 MB) up to 259522560 bytes (247 MB)
        JVM Flags: 0 total;
        IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
        FML: MCP v9.10 FML v8.99.8.1412 Minecraft Forge 11.14.1.1412 4 mods loaded, 4 mods active
        mcp{9.05} [Minecraft Coder Pack] (minecraft.jar) Unloaded->Constructed->Pre-initialized
        FML{8.99.8.1412} [Forge Mod Loader] (forge-1.8-11.14.1.1412-universal.jar) Unloaded->Constructed->Pre-initialized
        Forge{11.14.1.1412} [Minecraft Forge] (forge-1.8-11.14.1.1412-universal.jar) Unloaded->Constructed->Pre-initialized
        rpcraft{1.8.0-Beta 1.1} [RP Craft] (rpcraft-1.1-1.8.0.jar) Unloaded->Constructed->Errored
        Loaded coremods (and transformers):
        Profiler Position: N/A (disabled)
        Is Modded: Definitely; Server brand changed to 'fml,forge'
        Type: Dedicated Server (map_server.txt)