I have the same problem, just thought to look it up on here I only have to remove a block from one end, Tails I have a block under the tripwire on one end and it works its just the opposite end would not work with a block under it, so i tried a half slab and it works. In other words I have a part grounded and the rest in air. Im running 1.6.2 PC
Also realized this is happening in Vista for me
This may be related, I noticed mushrooms were lit in a dark cave
Ahh, I just posted this bug under dark chests, I've been having this problem as well.
Im having the same issue, i have a wall of item frames with crafting recipes, i leave the area and come back they are invisible. 1.8.1 Pre2 Windows Vista, I just saw it was resolved, guess not.