When I did my 2nd round of MC, I put them cigs up. I mean smoked them all until they were gone, didn't buy anymore and continued on the fast. I had no cravings what so ever while on my cleanse.
My only regret is that I ended up going back to them because of myself, not the cleanse, eating normal or any other reason, just me.
But I know that it can be done on the cleanse. Just make sure to keep doing the cleanse when you are done smoking at least for a while. What I noticed is that the cayenne pepper takes all of the mucous out that is caused by the cigs also. Which really helps a lot. The salt water helps flush the rest of the toxins out caused by the cigs also (amongst many other toxins).
So good luck to you. :)
When I get ready again, I'll be back for my 4th round and attempt to drop the smoking habit again. :D