I keep getting this crash report, anyone know the solution to it?

[hammersley]

---- Minecraft Crash Report ----

// You should try our sister game, Minceraft!

Time: 7/22/13 1:05 PM

Description: Exception in server tick loop

java.lang.NoClassDefFoundError: mods/immibis/core/porting/ClientProxy142

at java.lang.Class.forName0(Native Method)

at java.lang.Class.forName(Unknown Source)

at cpw.mods.fml.common.Loader.identifyMods(Loader.java:331)

at cpw.mods.fml.common.Loader.loadMods(Loader.java:486)

at cpw.mods.fml.server.FMLServerHandler.beginServerLoading(FMLServerHandler.java:86)

at cpw.mods.fml.common.FMLCommonHandler.onServerStart(FMLCommonHandler.java:350)

at net.minecraft.server.dedicated.DedicatedServer.func_71197_b(DedicatedServer.java:92)

at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:596)

at net.minecraft.server.ThreadMinecraftServer.run(ThreadMinecraftServer.java:16)

Caused by: java.lang.ClassNotFoundException: mods.immibis.core.porting.ClientProxy142

at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:179)

at java.lang.ClassLoader.loadClass(Unknown Source)

at java.lang.ClassLoader.loadClass(Unknown Source)

... 9 more

Caused by: java.lang.RuntimeException: Attempted to load class mods/immibis/core/porting/ClientProxy142 for invalid side SERVER

at cpw.mods.fml.common.asm.transformers.SideTransformer.transform(SideTransformer.java:50)

at net.minecraft.launchwrapper.LaunchClassLoader.runTransformers(LaunchClassLoader.java:267)

at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:165)

... 11 more

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

---------------------------------------------------------------------------------------

-- System Details --

Details:

Minecraft Version: 1.6.2

Operating System: Windows Server 2008 R2 (amd64) version 6.1

Java Version: 1.7.0_21, Oracle Corporation

Java VM Version: Java HotSpot 64-Bit Server VM (mixed mode), Oracle Corporation

Memory: 1807456232 bytes (1723 MB) / 2095185920 bytes (1998 MB) up to 3168927744 bytes (3022 MB)

JVM Flags: 4 total; -Xmx3G -Xms2G -XX:MaxPermSize=256M -Xincgc

AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used

Suspicious classes: FML and Forge are installed

IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0

CraftBukkit Information:

Running:

Failed to handle CraftCrashReport:

java.lang.NullPointerException

at org.bukkit.Bukkit.getName(Bukkit.java:72)

at org.bukkit.craftbukkit.v1_6_R2.CraftCrashReport.call(CraftCrashReport.java:19)

at net.minecraft.crash.CrashReportCategory.func_71500_a(CrashReportCategory.java:106)

at net.minecraft.crash.CrashReport.func_71504_g(CrashReport.java:58)

at net.minecraft.crash.CrashReport.<init>(CrashReport.java:40)

at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:655)

at net.minecraft.server.ThreadMinecraftServer.run(ThreadMinecraftServer.java:16)

FML: MCP v8.04 FML v6.2.30.794 Minecraft Forge 9.10.0.794 3 mods loaded, 0 mods active

mcp{8.04} [Minecraft Coder Pack] (minecraft.jar)

FML{6.2.30.794} [Forge Mod Loader] (coremods)

Forge{9.10.0.794} [Minecraft Forge] (coremods)

Profiler Position: N/A (disabled)

Is Modded: Definitely; Server brand changed to 'mcpc,craftbukkit,fml,forge'

Type: Dedicated Server (map_server.txt)