VDX_360":2el34nev said:
Quest items DO NOT APPEAR until the quest is triggered. Thus, the hammer should appear in the chest AFTER the quest is activated, not before.
This is not quite correct, at least in this case. The hammer DOES APPEAR even before the quest is active.
@Revenant: First, check the chest again. If it's not there, maybe you searched the chest beforehand and already have the hammer. Since it's a quest item, it cannot be sold or dropped, so check your vaults/chests/bag of holding. If you opened the chest but did not take the hammer, a warning should have appeared saying that you were about to leave a quest item behind. Did you notice any such warning? If yes and you ignored it, than the hammer may indeed be gone forever, rendering the quest impossible to complete. However, this wouldn't be a bug.
If none of the above mentioned things apply to your case, than there may indeed be some glitch, but let's first rule out the obvious causes.