[catlover]

I would say never call. If you are going to play, you should raise for three reasons:

(1) Your hand on average is better than the button's average hand.
(2) You want to put maximum pressure on the big blind to get out.
(3) By sometimes rasing and sometimes calling, you give away information about your hand. You want to avoid this, and can do so by always raising (or folding).

The question then becomes what do you raise with. I think your situation is pretty similar to the usual button stealing situation. When you steal on the button, you are raising against two random hands. You do not have a blind posted, but you have position. In your small blind situation, if the button is stealing 100% of the time, you are also raising against two random hands. You do not have position, but this is mitigated by the fact that you do have a blind posted. So whatever you would normally steal with, were you on the button, you should 3-bet here.

I think this is correct play on your part. Now if the big blind works out that you are doing this, he should start capping from the big blind with approximately the same hands that he would normally 3-bet from the small blind. That is, just as your situation is similar to a button steal situation, his situation is similar to a small bind defense. This is because the button, who is stealing 100% of the time, is basically like a "big blind". So it would be perfectly correct for him to cap with a hand like 66, or A9o, or 89s. (The last one is OK because, although it is weaker than your average hand, it is also stronger than the button's average hand.) And just as you should pursue a fold or 3-bet strategy to avoid giving away information, the big blind should fold or cap for the same reason.

The above presumes that the button really is stealing 100% of the time. If it's only 80%, you and the BB both need to tighten up.