Can't launch any modpacks

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Maybe you should list mods you are added or do we need to compare crashlog and official modlist?

[17:37:01] [main/INFO] [FastLeafDecay]: Found Leave Class: net/minecraft/block/BlockLeavesBase
[17:37:01] [main/INFO] [RandomThingsCore]: Found Leave Class: net/minecraft/block/BlockLeavesBase
...
Caused by: java.lang.NoClassDefFoundError: net/minecraft/block/BlockOldLeaf

Check those coremods. They are probably trying to do same thing
 
I am have added any mods to the core modpack for Infinity. This is only happening on my iMac and not on my windows based computer. I have installed 1.4.7 launcher.