[1.5.2] Client won't launch

[EntityCollision]

Hi,

 

I've set up my dev environment following the steps on the wiki:

http://www.minecraftforge.net/wiki/Forge_Development_in_IntelliJ_IDEA#For_Minecraft_1.5_and_earlier

 

But when I try to launch using the client configuration the launcher crashes.

Log: https://gist.github.com/Flightkick/9c8b4de423760f278691df62088cba2f

 

What could cause the ClassNotFoundExceptions and how may I be able to solve this?

 

Thanks in advance.

 

[Ernio]

Read my caption.

 

Seriously, I wouldn't even expect this to be answered. Sorry :C

 

Update!

[EntityCollision]

Ah I forgot to mention I am using 1.5.2 because I would like to make some changes to a Voltz mod (technic pack). This still runs on MC 1.5.2

I am aware that it won't be compatible with the newer MC versions but it is possible to develop mods for 1.5.2 so I was hoping someone recognized this error and was able to tell me what's going on.