This isn't a smoking or smoker's trights issue at all.
Most leases don't prohibit talking, but if a tenant talks so loudly the neighbors complain the landlord has the right to evict them.
I smoke, and i'm gearing up to quit, but I've always tried to be considerate of my smoking, ever since I quit once for a few months, and could finally smell the after-effects of smoking - us smokers simply can't smell it!
I live in an apartment, and will be for a while longer here in the wonderful and so very affordable San Francisco Bay Area housing market (sarcasm), and my downstairs neighbor, who's a good friend of mine, commented that my smoke gets blown right in her windows. So, I went and invested in one of those tower air filters, with ionizer, and run it when i'm home, problem solved! I bought bigger than I need, so it's very efficient at cleaning out the air. The ones the Sharper Image are the best, from what I'm told, but pricey - the one I got at Target was $60.
After using it for 6 months, I can't see NOT having one while continuing to smoke, and after - it removes cooking smells, dust, pollen, I love it! I have neighbors that smoke pot, which is just as pervasive as cigarette smoke, and it gives me an instant headache - no more!
A reasonable approach to heavy smokers would be to have the landlord provide a few filters like this, or contribute towards them. They work, nobody has to be evicted, and the heavy smokers will most likely love the cleaner air, along with their neighbors.
It also helps with that well-known side effect of smoking, where everything in the room where you smoke is covered in a layer of nicotine and residue. I HATE that, and since running my filters, there's very little of it.
Granted, I'm not a 3-pack a day smoker, but still...I'm frustrated and angry at the anti-smoking jihad, but there can be reasonable solutions, and us smokers can be considerate in close quarters.