This is in response to alot of theories i've read that seem to lead toward the thinking that MIB has always been in the cabin or was trapped in the cabin by the ash.
we all know that MIB is smokey, and we all know smokey cant pass a ring of ash. so why would everyone think that the ash kept MIB IN THE CABIN. we saw smokey rome the island freely throught the entire series, so if he was truly trapped in the cabin, how was smokey roming the island, impersonating dead ppl all while being trapped in the cabin.
i firmly disagree with that notion, when locke and ben visit the cabin it is Jacob that is in the cabin, and the ring of ash was keeping smokey away from him. once claire was claimed by MIB after her house blew up, christain takes her to the break the ash (thats my best guess) afterwords, Jacob realizes that MIB can now reach him and the cabin and he leaves it, MIB takes over the cabin, the locke hurley and ben find the cabin, and we all know the rest.
basically after jacob left the cabin he put the tapestry on the wall to alert ilana and bram that he has relocated to the statue, and he hasnt been here for a while, and they set the cabin on fire.
i also believe that the cave that Smocke (smokey/locke) takes sawyer is actually his home, not jacobs, he somehow got a hold of jacobs list and wrote them on his own wall and has been crossing names off ever since. if u look at the location of that cave, it clear with out a ladder the only thing that can get down there is a pillar of smoke, when hurley sees his imaginary friend dave, he jumps off that cliff, and when jack sees his dad he chases him off that cliff. (may not be the same cliff but could be argued).
and the way smokey would rise from underground is similar to where this cave is located to travel under the island surface and pop up when it needs to.
hopefully wat i wrote wasnt complicated i dont usually post theories i have too many in my head to post,
for instance, sawyers long con pt2,he cons smocke into thinking he's on his side, before finally betraying him to save the losties. stay tuned, take care.
id love to hear some feed back