I'm trying to make your mod work with the ones i already have but i always get this error:
---- Minecraft Crash Report ----
// Ouch. That hurt 
Time: 30-12-2012 8:55
Description: Failed to start game
java.lang.NullPointerException
at gravisuite.GraviSuite.getIC2Tab(GraviSuite.java:124)
at gravisuite.GraviSuite.load(GraviSuite.java:172)
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 cpw.mods.fml.common.FMLModContainer.handleModStateEvent(FMLModContainer.java:483)
at sun.reflect.GeneratedMethodAccessor3.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.google.common.eventbus.EventHandler.handleEvent(EventHandler.java:69)
at com.google.common.eventbus.SynchronizedEventHandler.handleEvent(SynchronizedEventHandler.java:45)
at com.google.common.eventbus.EventBus.dispatch(EventBus.java:317)
at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:300)
at com.google.common.eventbus.EventBus.post(EventBus.java:268)
at cpw.mods.fml.common.LoadController.propogateStateMessage(LoadController.java:140)
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.EventHandler.handleEvent(EventHandler.java:69)
at com.google.common.eventbus.SynchronizedEventHandler.handleEvent(SynchronizedEventHandler.java:45)
at com.google.common.eventbus.EventBus.dispatch(EventBus.java:317)
at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:300)
at com.google.common.eventbus.EventBus.post(EventBus.java:268)
at cpw.mods.fml.common.LoadController.distributeStateMessage(LoadController.java:83)
at cpw.mods.fml.common.Loader.initializeMods(Loader.java:656)
at cpw.mods.fml.client.FMLClientHandler.finishMinecraftLoading(FMLClientHandler.java:207)
at net.minecraft.client.Minecraft.a(Minecraft.java:456)
at asq.a(SourceFile:56)
at net.minecraft.client.Minecraft.run(Minecraft.java:744)
at java.lang.Thread.run(Unknown Source)
A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------
-- System Details --
Details:
Minecraft Version: 1.4.6
Operating System: Windows 7 (x86) version 6.1
Java Version: 1.7.0_09, Oracle Corporation
Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
Memory: 293431088 bytes (279 MB) / 519110656 bytes (495 MB) up to 1037959168 bytes (989 MB)
JVM Flags: 2 total; -Xms512m -Xmx1024m
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 v7.25 FML v4.6.15.514 Minecraft Forge 6.5.0.482 Optifine OptiFine_1.4.6_HD_U_A2 46 mods loaded, 46 mods active
mcp [Minecraft Coder Pack] (minecraft.jar) Unloaded->Constructed->Pre-initialized->Initialized
FML [Forge Mod Loader] (coremods) Unloaded->Constructed->Pre-initialized->Initialized
Forge [Minecraft Forge] (coremods) Unloaded->Constructed->Pre-initialized->Initialized
mod_CodeChickenCore [CodeChicken Core] (coremods) Unloaded->Constructed->Pre-initialized->Initialized
mod_InvTweaks [Inventory Tweaks] (minecraft.jar) Unloaded->Constructed->Pre-initialized->Initialized
snyke7_AdvancedMachines [Advanced Machines] (AdvancedMachines Original v1.8a.zip) Unloaded->Constructed->Pre-initialized->Initialized
Subaraki_ModBreeds [ModBreeds] (BB1.4.6 1.0.zip) Unloaded->Constructed->Pre-initialized->Initialized
BuildCraft|Core [BuildCraft] (buildcraft-A-3.3.0.jar) Unloaded->Constructed->Pre-initialized->Initialized
BuildCraft|Energy [BC Energy] (buildcraft-A-3.3.0.jar) Unloaded->Constructed->Pre-initialized->Initialized
BuildCraft|Factory [BC Factory] (buildcraft-A-3.3.0.jar) Unloaded->Constructed->Pre-initialized->Initialized
IC2 [IndustrialCraft 2] (industrialcraft-2_1.112.170-lf.jar) Unloaded->Constructed->Pre-initialized->Initialized
BCIC2Crossover [BC-IC2 Crossover Mod] (BCIC2crossover 2.0.zip) Unloaded->Constructed->Pre-initialized->Initialized
BuildCraft|Builders [BC Builders] (buildcraft-A-3.3.0.jar) Unloaded->Constructed->Pre-initialized->Initialized
BuildCraft|Transport [BC Transport] (buildcraft-A-3.3.0.jar) Unloaded->Constructed->Pre-initialized->Initialized
BuildCraft|Silicon [BC Silicon] (buildcraft-A-3.3.0.jar) Unloaded->Constructed->Pre-initialized->Initialized
ChargePads [Charge Pads] (chargepads-universal-2.3.0.58.zip) Unloaded->Constructed->Pre-initialized->Initialized
ChickenChunks [ChickenChunks] (ChickenChunks 1.2.1.0.jar) Unloaded->Constructed->Pre-initialized->Initialized
CompactSolars [Compact Solar Arrays] (compactsolars-universal-1.4.6-3.2.0.21.zip) Unloaded->Constructed->Pre-initialized->Initialized
craftguide [CraftGuide] (CraftGuide-1.6.5.12.zip) Unloaded->Constructed->Pre-initialized->Initialized
EnderStorage [EnderStorage] (EnderStorage 1.3.1.1.jar) Unloaded->Constructed->Pre-initialized->Initialized
BinnieCore [Binnie Core] (extrabees-1.4.9.5-prerelease-build.zip) Unloaded->Constructed->Pre-initialized->Initialized
ExtraBees [Extra Bees] (extrabees-1.4.9.5-prerelease-build.zip) Unloaded->Constructed->Pre-initialized->Initialized
ExtrabiomesXL [ExtrabiomesXL] (ExtrabiomesXL-universal-1.4.6-3.7.0a.jar) Unloaded->Constructed->Pre-initialized->Initialized
Forestry [Forestry for Minecraft] (forestry-A-1.6.4.2(8).jar) Unloaded->Constructed->Pre-initialized->Initialized
GraviSuite [Gravitation Suite] (GraviSuite_1_6.zip) Unloaded->Constructed->Pre-initialized->Errored
HangableMaps [Hangable Maps] (HangableMaps_v1.4.6_1_MC1.4.6.zip) Unloaded->Constructed->Pre-initialized->Initialized
IC2NuclearControl [Nuclear Control] (IC2NuclearControl-1.4.5.zip) Unloaded->Constructed->Pre-initialized->Initialized
IronChest [Iron Chest] (ironchest-universal-1.4.6-4.5.1.203.zip) Unloaded->Constructed->Pre-initialized->Initialized
LogisticsPipes|Main [Logistics Pipes] (LogisticsPipes-MC1.4.6-0.6.9.41.jar) Unloaded->Constructed->Pre-initialized->Initialized
ModularForceFieldSystem [Modular ForceField System V2] (ModularForceFieldSystemV2.2.8.2.13.zip) Unloaded->Constructed->Pre-initialized->Initialized
Mystcraft [Mystcraft] (mystcraft-uni-1.4.6-0.9.5.00.zip) Unloaded->Constructed->Pre-initialized->Initialized
PortalGun [Portal Gun] (portalgun1.4.6v2.zip) Unloaded->Constructed->Pre-initialized->Initialized
Railcraft [Railcraft] (Railcraft_1.4.6-6.12.2.0.zip) Unloaded->Constructed->Pre-initialized->Initialized
RedPowerCore [RedPower] (RedPowerCore-2.0pr6.zip) Unloaded->Constructed->Pre-initialized->Initialized
RedPowerBase [RP Base] (RedPowerCore-2.0pr6.zip) Unloaded->Constructed->Pre-initialized->Initialized
RedPowerMachine [RP Machine] (RedPowerMechanical-2.0pr6.zip) Unloaded->Constructed->Pre-initialized->Initialized
RedPowerCompat [RP Compat] (RedPowerCompat-2.0pr6.zip) Unloaded->Constructed->Pre-initialized->Initialized
RedPowerWiring [RP Wiring] (RedPowerDigital-2.0pr6.zip) Unloaded->Constructed->Pre-initialized->Initialized
RedPowerLogic [RP Logic] (RedPowerDigital-2.0pr6.zip) Unloaded->Constructed->Pre-initialized->Initialized
RedPowerLighting [RP Lighting] (RedPowerDigital-2.0pr6.zip) Unloaded->Constructed->Pre-initialized->Initialized
RedPowerWorld [RP World] (RedPowerMechanical-2.0pr6.zip) Unloaded->Constructed->Pre-initialized->Initialized
RedPowerControl [RP Control] (RedPowerMechanical-2.0pr6.zip) Unloaded->Constructed->Pre-initialized->Initialized
Thaumcraft [Thaumcraft] (Thaumcraft3.0.1c.zip) Unloaded->Constructed->Pre-initialized->Initialized
WR-CBE|Core [WR-CBE Core] (WR-CBE Core 1.3.2.2.jar) Unloaded->Constructed->Pre-initialized->Initialized
WR-CBE|Addons [WR-CBE Addons] (WR-CBE Addons 1.3.2.2.jar) Unloaded->Constructed->Pre-initialized->Initialized
WR-CBE|RedPower [WR-CBE RedPower] (WR-CBE RedPower 1.3.2.2.jar) Unloaded->Constructed->Pre-initialized->Initialized
LWJGL: 2.4.2
OpenGL: AMD Radeon HD 7800 Series GL version 4.2.11931 Compatibility Profile Context, ATI Technologies Inc.
Is Modded: Definitely; Client brand changed to 'forge,fml'
Type: Client (map_client.txt)
Texture Pack: Sphax PureBDCraft 64x MC14.zip
Profiler Position: N/A (disabled) Vec3 Pool Size: ~~ERROR~~ NullPointerException: null
If you could help me, I would appreciate it 
Thanks in advance