Problème d'installation du mod buildcraft

Bonjour,
j'ai voulu installer le mod buildcraft sur minecraft j'ai donc télécharger les lien et les ai installer et quand je lance le jeu après mojang j'ai un message d'erreur me disant que minecraft a cracher :

1 mod loaded
Minecraft Forge 3.3.8.152
FML v2.2.78.153
Forge Mod Loader version 2.2.78.153 for Minecraft 1.2.5
mod_ModLoaderMp : Loaded (minecraft.jar)


Minecraft has crashed!
----------------------

Minecraft has stopped running because it encountered a problem.




--- BEGIN ERROR REPORT 6dced9bb --------
Generated 30/07/12 06:49

Minecraft: Minecraft 1.2.5
OS: Windows XP (x86) version 5.1
Java: 1.6.0_30, Sun Microsystems Inc.
VM: Java HotSpot(TM) Client VM (mixed mode), Sun Microsystems Inc.
LWJGL: 2.4.2
OpenGL: GeForce 8600 GT/PCI/SSE2/3DNOW! version 2.1.2, NVIDIA Corporation

cpw.mods.fml.common.LoaderException: cpw.mods.fml.common.LoaderException: java.lang.VerifyError: (class: kq, method: b signature: (Ljava/lang/String;)Lfd;) Wrong return type in function
at cpw.mods.fml.common.Loader.load(Loader.java:436)
at cpw.mods.fml.common.Loader.loadMods(Loader.java:592)
at cpw.mods.fml.client.FMLClientHandler.onPreLoad(FMLClientHandler.java:193)
at net.minecraft.client.Minecraft.a(Minecraft.java:383)
at net.minecraft.client.Minecraft.run(Minecraft.java:735)
at java.lang.Thread.run(Unknown Source)
Caused by: cpw.mods.fml.common.LoaderException: java.lang.VerifyError: (class: kq, method: b signature: (Ljava/lang/String;)Lfd;) Wrong return type in function
at cpw.mods.fml.common.Loader.loadModClass(Loader.java:527)
at cpw.mods.fml.common.Loader.attemptFileLoad(Loader.java:561)
at cpw.mods.fml.common.Loader.load(Loader.java:382)
... 5 more
Caused by: java.lang.VerifyError: (class: kq, method: b signature: (Ljava/lang/String;)Lfd;) Wrong return type in function
at f.a(SourceFile:25)
at f.b(SourceFile:16)
at afl.b(SourceFile:36)
at la.<init>(SourceFile:66)
at nv.a(SourceFile:64)
at nv.b(SourceFile:22)
at wn.a(SourceFile:42)
at wn.b(SourceFile:19)
at acr.a(SourceFile:27)
at fw.a(SourceFile:37)
at cpw.mods.fml.client.FMLClientHandler.readMetadataFrom(FMLClientHandler.java:795)
at cpw.mods.fml.common.FMLCommonHandler.loadMetadataFor(FMLCommonHandler.java:509)
at cpw.mods.fml.common.Loader.loadModClass(Loader.java:518)
... 7 more
--- END ERROR REPORT b58476da ----------
pourriez vous me donner des solution pour pouvoir installer ce mod sil vous plait car cela fait déjà plusieurs heur que je passe a essayer de résoudre se problème. merci d'avance