I've been using comparators to sense the inventory of hoppers to create a basic sorting system. Simple stuff. I've noticed, however, that if the chunk that the Comparator is in becomes unloaded, the comparator is frozen in its state and will not update if the amount of items in the inventory changes. It will only update when the comparator recieves a block update.

What I expected to happen was...:
When I came back to the chunk with the comparator, I expected that it would work without my having to update it.

What actually happened was...:
The comparator would not detect inventory changes unless it was updated.

Steps to Reproduce
1) Place a chest with a comparator coming out the back of it. Set up some redstone to indicate inventory level.
2) Place one item in the chest.
3) Leave the area and travel far enough away for the chunk to unload. Logging out and in will not cause the unload.
4) Remain outside the area for a few minutes, then return to the comparator.
5) Place several stacks of items in the chest. You will note that the comparator's signal does not update.
6) Place a block beside the comparator, causing an update. The comparator's signal strength will nwo correctly display.