loading error

[Colin_L]

so i felt like playing minecraft this morning and my tekket folder was not working as it poped up with a loading error, this problem has probably occurred before so i am sorry for reposting it. i run on MAC OS X, can someone please help

this is the error that poped up...

Mods loaded: 16

ModLoader 1.2.5

mod_MinecraftForge 3.1.3.107

mod_CodeChickenCore 0.5.2

mod_NotEnoughItems 1.2.2

mod_IC2AdvancedMachines v4.0

mod_CCTurtle 1.33

mod_ComputerCraft 1.33

mod_CraftingTableIII (Beta1.8, MC1.2.5)

mod_EE 1.4.5.1

mod_EnderStorage 1.1.1

mod_IC2NuclearControl v1.1.6

mod_InvTweaks 1.41b (1.2.4)

mod_MAtmos_forModLoader r12 for 1.1.x

mod_NetherOres 1.2.5R1.2.2

mod_PowerConverters 1.2.5R1.3.4

mod_Railcraft 5.2.0

Minecraft has crashed!

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

Minecraft has stopped running because it encountered a problem.

--- BEGIN ERROR REPORT 2cdf6d7f --------

Generated 5/27/12 8:33 AM

Minecraft: Minecraft 1.2.5

OS: Mac OS X (x86_64) version 10.6.8

Java: 1.6.0_31, Apple Inc.

VM: Java HotSpot 64-Bit Server VM (mixed mode), Apple Inc.

LWJGL: 2.4.2

OpenGL: NVIDIA GeForce GT 330M OpenGL Engine version 2.1 NVIDIA-1.6.40, NVIDIA Corporation

RailcraftInstallationException: Railcraft Client 5.2.0: Mulitple versions found!

************************************************************************************

Railcraft is already loaded, please check your mod folder for old versions.

************************************************************************************

--- END ERROR REPORT 617e29c1 ----------

[sct]

Why are you using the tekkit dev build?