I installed Rocket Science to Technic SSP( mod list: http://www.technicpack.net/technic6/) and it generated this error:
Mods loaded: 39
ModLoader 1.2.5
mod_CodeChickenCore 0.5.2
mod_MinecraftForge 3.1.2.94
mod_NotEnoughItems 1.2.2
mod_betterDungeons 0.931
mod_crystalWing 1.2.5.a updated by bspkrs
mod_EE 1.4.4.0
mod_EnderStorage 1.1.1
mod_InvTweaks 1.41b (1.2.4)
mod_Railcraft 5.1.0
mod_IC2 v1.95
mod_RedPowerControl 2.0pr5b1
mod_RedPowerCore 2.0pr5b1
mod_RedPowerLighting 2.0pr5b1
mod_RedPowerLogic 2.0pr5b1
mod_RedPowerMachine 2.0pr5b1
mod_RedPowerWiring 2.0pr5b1
mod_RedPowerWorld 2.0pr5b1
mod_ZZZMissile 0.89
mod_treecapitator 1.2.5.e updated by bspkrs
mod_WirelessRedstoneCore 1.2.0
mod_WirelessRedstoneRedPower 1.2.0
mod_WirelessRedstoneAddons 1.2.0
Balkon's WeaponMod 1.2.5 v8.6.0
mod_Somnia v24 [1.2.5]
mod_ReiMinimap v3.0_04 [1.2.5]
mod_BuildCraftCore 3.1.5
mod_BuildCraftBuilders 3.1.5
mod_BuildCraftEnergy 3.1.5
mod_BuildCraftFactory 3.1.5
mod_BuildCraftTransport 3.1.5
mod_AdditionalPipes 3.0.10 (Minecraft 1.2.5, Buildcraft 3.1.5, Forge 3.1.2.93)
mod_LogisticsPipes 0.2.4 (built with Minecraft 1.2.5, Buildcraft 3.1.5, Forge 3.1.2.90)
mod_BuildCraftSilicon 3.1.5
mod_IC2 v1.95
mod_Millenaire 2.5.9
mod_lectern 1.2.5
mod_xpbook 1.2.5
mod_ThaumCraft 2.1.1a
Minecraft has crashed!
----------------------
Minecraft has stopped running because it encountered a problem.
--- BEGIN ERROR REPORT 5d4a648e --------
Generated 6/16/12 3:32 PM
Minecraft: Minecraft 1.2.5
OS: Mac OS X (x86_64) version 10.7.4
Java: 1.6.0_31, Apple Inc.
VM: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Apple Inc.
LWJGL: 2.4.2
OpenGL: ATI Radeon HD 4850 OpenGL Engine version 2.1 ATI-7.18.18, ATI Technologies Inc.
java.lang.IllegalArgumentException: Slot 249 is already occupied by ic2.common.BlockTex@6205320 when adding ic2.common.BlockTex@34315d04
at pb.<init>(Block.java:249)
at pb.<init>(Block.java:281)
at ic2.platform.BlockCommon.<init>(BlockCommon.java:12)
at ic2.common.BlockTex.<init>(BlockTex.java:30)
at mod_IC2.load(mod_IC2.java:154)
at ModLoader.init(ModLoader.java:891)
at ModLoader.addAllRenderers(ModLoader.java:189)
at ahu.<init>(ahu.java:77)
at ahu.<clinit>(ahu.java:8)
at net.minecraft.client.Minecraft.a(Minecraft.java:394)
at net.minecraft.client.Minecraft.run(Minecraft.java:732)
at java.lang.Thread.run(Thread.java:680)
--- END ERROR REPORT c6b5fa39 ----------