I was testing some issues for #809 by placing some pipes, and somehow this happened:
http://pastebin.com/bW8F4bEq

Are you using the new or the old renderer?
Have you played around with your texture packs before the crash?

Actually it was the old renderer, for some reason. I didn't touched any settings, just installed the mods into a new instance of Minecraft.
No, I'm not using any texture packs.