Common situation, LAG donks river in apparent bluff.

[Intent]

sb is a 66/22. I've seen him make serious bluffs before, and I think he's bluffing now. I feel my read on him is pretty good, and I'm quite sure he doesn't have a 3. I think he's donking me with some random unpaired hand in a kind of desperation bluff. But all the same, can I raise here? He's such a LAG I think I have to call a 3 bet. And I'm not positive he calls me with a worse hand.

I feel like this situation comes up fairly often. I talked to two people about it on AIM, and we couldn't come up with a consensus.

Party Poker 3/6 Hold'em (6 max, 6 handed) converter

Preflop: Hero is BB with 9[img]/images/graemlins/diamond.gif[/img], T[img]/images/graemlins/diamond.gif[/img].
<font color="#666666">1 fold</font>, MP calls, <font color="#666666">2 folds</font>, SB completes, Hero checks.

Flop: (3 SB) 7[img]/images/graemlins/heart.gif[/img], 3[img]/images/graemlins/diamond.gif[/img], 4[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(3 players)</font>
SB checks, Hero checks, MP checks.

Turn: (1.50 BB) 9[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(3 players)</font>
SB checks, <font color="#CC3333">Hero bets</font>, MP folds, SB calls.

River: (3.50 BB) 3[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">SB bets</font>, Hero ...

Final Pot: 5.50 BB