used Versions:
Minecraft 1.7.10
Forge: 1.7.10-Forge10.13.0.1208
Mekanism: 1.7.10-7.1.0.90
Forestry: 1.7.10-3.0.0.90

Crashlog

---- Minecraft Crash Report ----
// Quite honestly, I wouldn't worry myself about that.

Time: 8/24/14 12:52 PM
Description: Exception in server tick loop

java.lang.NoClassDefFoundError: Lic2/api/energy/prefab/BasicSink;
at java.lang.Class.getDeclaredFields0(Native Method)
at java.lang.Class.privateGetDeclaredFields(Class.java:2436)
at java.lang.Class.getDeclaredFields(Class.java:1806)
at buildcraft.api.core.JavaTools.getAllFields(JavaTools.java:59)
at buildcraft.api.mj.MjAPI.getMjBatteryField(MjAPI.java:196)
at buildcraft.api.mj.MjAPI.getMjBattery(MjAPI.java:85)
at buildcraft.api.mj.MjAPI.getMjBattery(MjAPI.java:55)
at buildcraft.api.mj.MjAPI.getMjBattery(MjAPI.java:46)
at mekanism.common.util.CableUtils.isEnergyAcceptor(CableUtils.java:56)
at mekanism.common.util.CableUtils.getConnectedEnergyAcceptors(CableUtils.java:45)
at mekanism.common.EnergyNetwork.refresh(EnergyNetwork.java:335) at mekanism.common.multipart.PartTransmitter.refreshTransmitterNetwork(PartTransmitter.java:42)
at mekanism.common.multipart.PartUniversalCable.refreshTransmitterNetwork(PartUniversalCable.java:134) at TGridTransmitter$$3$class.refreshTransmitterNetwork(Unknown Source)
at TileMultipart_cmp$$21.refreshTransmitterNetwork(Unknown Source)
at mekanism.api.transmitters.TransmitterNetworkRegistry$NetworkLoader.refreshChunk(TransmitterNetworkRegistry.java:150) at mekanism.api.transmitters.TransmitterNetworkRegistry$NetworkLoader.onChunkLoad(TransmitterNetworkRegistry.java:132)
at cpw.mods.fml.common.eventhandler.ASMEventHandler_97_NetworkLoader_onChunkLoad_Load.invoke(.dynamic)
at cpw.mods.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:51)
at cpw.mods.fml.common.eventhandler.EventBus.post(EventBus.java:122) at net.minecraft.world.chunk.Chunk.func_76631_c(Chunk.java:1019)
at net.minecraftforge.common.chunkio.ChunkIOProvider.callStage2(ChunkIOProvider.java:49) at net.minecraftforge.common.chunkio.ChunkIOProvider.callStage2(ChunkIOProvider.java:15)
at net.minecraftforge.common.util.AsynchronousExecutor.skipQueue(AsynchronousExecutor.java:344) at net.minecraftforge.common.util.AsynchronousExecutor.getSkipQueue(AsynchronousExecutor.java:302)
at net.minecraftforge.common.chunkio.ChunkIOExecutor.syncChunkLoad(ChunkIOExecutor.java:12) at net.minecraft.world.gen.ChunkProviderServer.loadChunk(ChunkProviderServer.java:164)
at net.minecraft.world.gen.ChunkProviderServer.func_73158_c(ChunkProviderServer.java:137) at net.minecraft.server.MinecraftServer.func_71222_d(MinecraftServer.java:469)
at net.minecraft.server.MinecraftServer.func_71247_a(MinecraftServer.java:434)
at net.minecraft.server.dedicated.DedicatedServer.func_71197_b(DedicatedServer.java:329)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:620)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.ClassNotFoundException: ic2.api.energy.prefab.BasicSink
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:99)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
... 33 more

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

-- System Details --
Details:
Minecraft Version: 1.7.10
Operating System: Linux (amd64) version 2.6.32-431.20.3.el6.x86_64
Java Version: 1.7.0_65, Oracle Corporation
Java VM Version: OpenJDK 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 2593745536 bytes (2473 MB) / 3736600576 bytes (3563 MB) up to 7635730432 bytes (7282 MB)
JVM Flags: 2 total; -Xms2G -Xmx8G
AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
IntCache: cache: 1, tcache: 0, allocated: 12, tallocated: 96
FML: MCP v9.05 FML v7.10.25.1207 Minecraft Forge 10.13.0.1207 61 mods loaded, 61 mods active
mcp{9.05} Minecraft Coder Pack Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
FML{7.10.25.1207} Forge Mod Loader Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
Forge{10.13.0.1207} Minecraft Forge Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
appliedenergistics2-core{rv1-beta-10} AppliedEnergistics2 Core Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
CodeChickenCore{1.0.3.23} CodeChicken Core Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
{000} CoFH ASM Data Initialization Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
appliedenergistics2{rv1-beta-10} Applied Energistics 2 Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
BiblioCraft{1.7.5} BiblioCraft Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
BuildCraft|Core{6.0.17} BuildCraft Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
Forestry{3.0.0.90} Forestry for Minecraft Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
BiblioWoodsForestry{1.5} BiblioWoods Forestry Edition Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
BuildCraft|Builders{6.0.17} BC Builders Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
BuildCraft|Energy{6.0.17} BC Energy Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
BuildCraft|Factory{6.0.17} BC Factory Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
BuildCraft|Transport{6.0.17} BC Transport Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
BuildCraft|Silicon{6.0.17} BC Silicon Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
CarpentersBlocks{3.2.6} Carpenter's Blocks Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
CoFHCore{1.7.10R3.0.0B5} CoFH Core Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
ComputerCraft{1.64pr4} ComputerCraft Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
ImmibisCore{59.0.1} Immibis Core Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
DimensionalAnchors{59.0.2} Dimensional Anchors Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
EnderStorage{1.4.5.20} EnderStorage Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
IronChest{6.0.41.729} Iron Chest Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
MineFactoryReloaded{1.7.10R2.8.0RC2} MineFactory Reloaded Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
UniversalElectricity{@major@.@minor@.@revis@} Universal Electricity Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Availabl
e
ForgeMultipart{1.1.0.297} Forge Multipart Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
Mekanism{7.1.0} Mekanism Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
MekanismGenerators{7.1.0} MekanismGenerators Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
MekanismTools{7.1.0} MekanismTools Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
MineFactoryReloaded|CompatAppliedEnergistics{1.7.10R2.8.0RC2} MFR Compat: Applied Energistics Unloaded->Constructed->Pre-initialized->Initialized->Post-initializ
ed->Available->Available
MineFactoryReloaded|CompatAtum{1.7.10R2.8.0RC2} MFR Compat: Atum Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
MineFactoryReloaded|CompatBackTools{1.7.10R2.8.0RC2} MFR Compat: BackTools Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Avai
lable
MineFactoryReloaded|CompatBuildCraft{1.7.10R2.8.0RC2} MFR Compat: BuildCraft Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Av
ailable
MineFactoryReloaded|CompatChococraft{1.7.10R2.8.0RC2} MFR Compat: Chococraft Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Av
ailable
MineFactoryReloaded|CompatExtraBiomes{1.7.10R2.8.0RC2} MFR Compat: ExtraBiomes Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->
Available
MineFactoryReloaded|CompatForestry{1.7.10R2.8.0RC2} MFR Compat: Forestry Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Availa
ble
MineFactoryReloaded|CompatForgeMicroblock{1.7.10R2.8.0RC2} MFR Compat: ForgeMicroblock Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Ava
ilable->Available
MineFactoryReloaded|CompatIC2{1.7.10R2.8.0RC2} MFR Compat: IC2 Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
MineFactoryReloaded|CompatMystcraft{1.7.10R2.8.0RC2} MFR Compat: Mystcraft Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Avai
lable
MineFactoryReloaded|CompatPams{1.7.10R2.8.0RC2} MFR Compat: Pam's Mods Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Availabl
e
ProjRed|Core{4.4.6.45} ProjectRed Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
ProjRed|Exploration{4.4.6.45} ProjectRed-Exploration Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
MineFactoryReloaded|CompatProjRed{1.7.10R2.8.0RC2} MFR Compat ProjectRed Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Availa
ble
MineFactoryReloaded|CompatRailcraft{1.7.10R2.8.0RC2} MFR Compat: Railcraft Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Avai
lable
MineFactoryReloaded|CompatRP2{1.7.10R2.8.0RC2} MFR Compat: RP2 Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
MineFactoryReloaded|CompatSufficientBiomes{1.7.10R2.8.0RC2} MFR Compat: Sufficient Biomes Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->
Available->Available
MineFactoryReloaded|CompatThaumcraft{1.7.10R2.8.0RC2} MFR Compat: Thaumcraft Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Av
ailable
MineFactoryReloaded|CompatThermalExpansion{1.7.10R2.8.0RC2} MFR Compat: Thermal Expansion Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->
Available->Available
TwilightForest{2.2.3} The Twilight Forest Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
MineFactoryReloaded|CompatTwilightForest{1.7.10R2.8.0RC2} MFR Compat: TwilightForest Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Avail
able->Available
MineFactoryReloaded|CompatVanilla{1.7.10R2.8.0RC2} MFR Compat: Vanilla Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Availabl
e
cfm{3.3.5} §6MrCrayfish's Furniture Mod Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
NetherOres{1.7.10R2.3.0RC3} Nether Ores Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
ProjRed|Transmission{4.4.6.45} ProjectRed-Transmission Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
ProjRed|Compatibility{4.4.6.45} ProjectRed-Compatibility Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
ProjRed|Integration{4.4.6.45} ProjectRed-Integration Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
ProjRed|Illumination{4.4.6.45} ProjectRed-Illumination Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
stillhungry{1.7.2-2.1.0} Still Hungry! Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
ThermalFoundation{1.7.10R1.0.0B3} Thermal Foundation Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
McMultipart{1.1.0.297} Minecraft Multipart Plugin Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
ForgeMicroblock{1.1.0.297} Forge Microblocks Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
AE2 Version: beta rv1-beta-10 for Forge 10.13.0.1187
AE2 Integration: IC2:OFF, RotaryCraft:OFF, RC:OFF, BC:ON, MJ6:ON, MJ5:ON, RF:ON, RFItem:ON, MFR:ON, DSU:ON, FZ:OFF, FMP:ON, RB:OFF, CLApi:OFF, Mekanism:ON, ImmibisMicroblocks:OFF, BetterStorage:OFF
Forestry : [Forestry] Warning: You have mods that change the behavior of Minecraft, ForgeModLoader, and/or Minecraft Forge to your client:
Bukkit, MCPC+, or other Bukkit replacement
These may have caused this error, and may not be supported. Try reproducing the crash WITHOUT these mods, and report it then.
Profiler Position: N/A (disabled)
Vec3 Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
Player Count: 0 / 20; []
Is Modded: Definitely; Server brand changed to 'cauldron,craftbukkit,mcpc,fml,forge'
Type: Dedicated Server (map_server.txt)

A mod is shipping with the IC2 API. Not a Mekanism bug.

okay thanks for this information. i'll try to find the mod who are generates this bug :-)