Signs With Symbols Crash

I was playing around with the /setblock command in Minecraft 13w42a and I was creating signs that had symbols you can't normally type (I copied & pasted them in chat) without doing alt codes. Here's the command I used in Minecraft 13w42a:

/setblock ~0 ~1 ~0 minecraft:wall_sign 4 replace {Text2:"ℤ℮ℛℴ’ϟ Skull",Text3:"100 Points"}

I noticed that Minecraft 13w42b came out with 0.02% less bugs including changes to do with more text support for signs. When I downloaded that & played my world, the game just crashes. I would post the crash log but it thinks the game is modded for some reason.