Starting a new world works fine, but i'll get this crash after loading (upgraded from #239) my creative flat with lots of machines.
Deleted all configs, also ic2map.cfg, same result.
Display Spoiler
---- Minecraft Crash Report ----
// Hi. I'm Minecraft, and I'm a crashaholic.
Time: 07.10.13 16:09
Description: Exception in server tick loop
java.lang.NoClassDefFoundError: org/ejml/data/Matrix64F
	at ic2.core.energy.EnergyNetLocal.addTileToGrids(EnergyNetLocal.java:343)
	at ic2.core.energy.EnergyNetLocal.addTileEntity(EnergyNetLocal.java:119)
	at ic2.core.energy.EventHandler.onEnergyTileLoad(EventHandler.java:26)
	at net.minecraftforge.event.ASMEventHandler_29_EventHandler_onEnergyTileLoad_EnergyTileLoadEvent.invoke(.dynamic)
	at net.minecraftforge.event.ASMEventHandler.invoke(ASMEventHandler.java:39)
	at net.minecraftforge.event.EventBus.post(EventBus.java:108)
	at ic2.core.block.wiring.TileEntityCable.onLoaded(TileEntityCable.java:135)
	at ic2.core.block.TileEntityBlock$1.tickCallback(TileEntityBlock.java:53)
	at ic2.core.IC2.processTickCallbacks(IC2.java:1660)
	at ic2.core.IC2.tickStart(IC2.java:1510)
	at cpw.mods.fml.common.SingleIntervalHandler.tickStart(SingleIntervalHandler.java:28)
	at cpw.mods.fml.common.FMLCommonHandler.tickStart(FMLCommonHandler.java:122)
	at cpw.mods.fml.common.FMLCommonHandler.onPreWorldTick(FMLCommonHandler.java:295)
	at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:650)
	at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:585)
	at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:129)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:482)
	at net.minecraft.server.ThreadMinecraftServer.run(SourceFile:582)
Caused by: java.lang.ClassNotFoundException: org.ejml.data.Matrix64F
	at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:179)
	at java.lang.ClassLoader.loadClass(Unknown Source)
	at java.lang.ClassLoader.loadClass(Unknown Source)
	... 18 more
Caused by: java.lang.NullPointerException
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 7 (amd64) version 6.1
	Java Version: 1.7.0_05, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 41806600 bytes (39 MB) / 453705728 bytes (432 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
	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
	FML: MCP v8.04 FML v6.2.62.871 Minecraft Forge 9.10.1.871 24 mods loaded, 24 mods active
	mcp{8.04} [Minecraft Coder Pack] (minecraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	FML{6.2.62.871} [Forge Mod Loader] (minecraftforge-9.10.1.871.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	Forge{9.10.1.871} [Minecraft Forge] (minecraftforge-9.10.1.871.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	AppliedEnergistics-Core{rv13.c} [AppliedEnergistics Core] (minecraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	CodeChickenCore{0.9.0.5} [CodeChicken Core] (minecraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	NotEnoughItems{1.6.1.4} [Not Enough Items] (NotEnoughItems 1.6.1.4.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	mod_ReiMinimap{v3.4_01 [1.6.2]} [mod_ReiMinimap] ([1.6.2]ReiMinimap_v3.4_01.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	AppliedEnergistics{rv13.c} [Applied Energistics] (appeng-rv13-c-mc162.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	Backpack{1.18.17} [Backpack] (backpack-1.18.17-1.6.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	BuildCraft|Core{4.0.2} [BuildCraft] (buildcraft-A-4.0.2.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	BuildCraft|Builders{4.0.2} [BC Builders] (buildcraft-A-4.0.2.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	BuildCraft|Energy{4.0.2} [BC Energy] (buildcraft-A-4.0.2.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	BuildCraft|Factory{4.0.2} [BC Factory] (buildcraft-A-4.0.2.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	BuildCraft|Transport{4.0.2} [BC Transport] (buildcraft-A-4.0.2.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	BuildCraft|Silicon{4.0.2} [BC Silicon] (buildcraft-A-4.0.2.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	craftguide{1.5.2} [CraftGuide] (CraftGuide-1.6.7.4.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	IC2{2.0.249-experimental} [IndustrialCraft 2] (industrialcraft-2_2.0.249-experimental.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	Railcraft{8.1.0.0} [Railcraft] (Railcraft_1.6.2-8.1.0.0.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	gregtech_addon{MC162} [GregTech-Addon] (gregtechmod.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	Highlands{2.1.1} [Highlands] (Highlands2.1.2_MC1.6.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	IC2NuclearControl{1.6.2c} [Nuclear Control] (IC2NuclearControl-1.6.2c-ic2-experimental.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	mod_Xray{MX for 1.6.2} [mod_Xray] (mod_XrayV1.11.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	GraviSuite{1.9.6} [Gravitation Suite] (mod_zGraviSuite_1_9_6_IC2_EXP.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	TC{4.1.1_001} [Traincraft] (traincraft-4.1.1_001.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	Player Count: 0 / 8; []
	Type: Integrated Server (map_client.txt)
	Is Modded: Definitely; Client brand changed to 'fml,forge'
€dit: Found it in the bugtracker now (was down for me).
Thread ready for the bin :p
 
		