Crash caused by vertical wiring (half slabs / glowstone / full blocks)

To reproduce:
1. Build vertical wiring "stairs" using half-slabs (or glowstone, by some reports and full blocks MC-10469)
2. Wiring should be high enough, atleast 16 blocks total.
3. Tests show that this happens most likely when wiring is aligned along X axis.
4. Trying to input redstone signal at one of the sides (usually from where X is greater) at certain height (usually closer to the top) will crash the game.
5. If you are able to relog, you will observe invalid signal travelling downwards, as in second screenshot.

Video: http://youtu.be/AZPw2Cmm9DQ

Old description:
1. Placed the redstone torch on a side of a block in certain position.
2. The redstone torch appeared, in ON state (although it should be off because the block is powered, but usually they go off in a moment).
3. The game crashed before I could do anything else.
4. Reentered the world, torch was still ON, game crashed immediately.
5. Reentered the world, torch was OFF, and game didn't seem to crash.
6. Broke the torch, didn't seem to crash.
7. Placed it again, another crash.
Since the issue seems reproducable in certain configurations only, the world save file is attached, as well as crash reports. The torch in question is the one my player is facing as per save file. Try breaking it and placing again to reproduce.