unethical to exploit disconnected player?

[easternbloc]

during a recent sng I played, the following situation came up (approximately):



player1: 2000
player2: 2000
me: 7000
disconnected player: 1000


the blinds were 100/200 and I proceeded to push every hand and fold to the player when he was in the big blind. my reasoning is that this is optimal play if both player 1 and 2 are playing mainly to make the money (which I had observed prior to disconnection) and if the player who was disconnected was instead connected but for some reason folding every hand.

my questions are
a) would you consider this against the rules? (the poker site in question was pokerstars)
b) was this an unethical thing to do?