Whenever I place on sign on a fence, whether the side or top, I cannot edit the sign with text. I can edit the sign on the ground, or on other blocks, but not fence. I am getting this problem in both single player and on my server in multiplayer. It also will not let me edit on Nether Brick fence. It will let me edit on anything else though, even Iron Bars. I use 64 bit Java and my friend uses 32 bit Java, and he has the same issue.