Minecraft Mod Manager

Son #1 has got hugely into Minecraft recently. As a result son #2 is now interested in it also, but that's a different story. I've been roped in as the tech support to install all the "mods". Installing mods involves unpacking and repacking the contents of the minecraft.jar file and moving resources about in your minecraft folder. This is too tricky for a nine-year-old to do reliably at the moment. I've started writing a python script to automate the process. I had a quick goolge to see if I could find someone solving this problem already but didn't find anything.