I can't launch MC 1.2.5, it fails with

Loading current icons for window from: icons/icon_16x16.png and icons/icon_32x32.png
javax.imageio.IIOException: Can't read input file!
at javax.imageio.ImageIO.read(ImageIO.java:1301)
at net.minecraft.launchwrapper.injector.VanillaTweakInjector.loadIcon(VanillaTweakInjector.java:130)
at net.minecraft.launchwrapper.injector.VanillaTweakInjector.loadIconsOnFrames(VanillaTweakInjector.java:107)
at net.minecraft.launchwrapper.injector.VanillaTweakInjector.inject(VanillaTweakInjector.java:94)
at net.minecraft.client.Minecraft.main(SourceFile:2136)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:57)
at net.minecraft.launchwrapper.Launch.main(Launch.java:18)

i can't find these files in pre 1.6 assets json