I see that our Devs may forgot to update that String. Its Forge 3.3.7.135.
I dropped all the files of Minecraft Forge 3.3.7.135. into my minecraft.jar, deleted META-INF and placed Modloader and IC2 1.97 in my mods folders, I now get a black screen...
EDIT:
I also tried placing the modloader files into the minecraft.jar and nothing changed 
--- BEGIN ERROR REPORT 1a3703ac --------Generated 17/07/12 02:03 AM
Minecraft: Minecraft 1.2.5OS: Windows 7 (amd64) version 6.1Java: 1.7.0_02, Oracle CorporationVM: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle CorporationLWJGL: 2.4.2OpenGL: GeForce GT 240/PCI/SSE2 version 3.2.0, NVIDIA Corporation
java.lang.RuntimeException: IndustrialCraft 2: MinecraftForge Too Old, need at least 3.1.2 at forge.MinecraftForge.killMinecraft(MinecraftForge.java:449) at forge.MinecraftForge.versionDetect(MinecraftForge.java:468) at mod_IC2.load(mod_IC2.java:36) 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(Unknown Source)--- END ERROR REPORT 57294a80 ----------I had other mods installed, I removed them from the mods section and it still didn't worked, I also installed Minecraft Forge 3.1.2 again and nothing seemed to change. :c
Modloader and ModloaderMP are installed (Doublechecked)