I cannot complete the quest "A Man Who Cried Wolf." The large hole that is supposed to be in the cave is covered in weird, gray ice. Does anyone know what's causing this?

http://i.imgur.com/BlZ0t.jpg

Odd, i was just there... but i think i have seen that ice, you started the quest by talking to the guy in Blue Palace? maybe the hole dosent appears untill you start the quest.