Weird two pair spot in multiway limped pot

[FoxwoodsFiend]

SB is a multitabling regular. He tanked for a few seconds before calling. UTG is a totally unknown new player. Thoughts on how I played the hand throughout?

Full Tilt Poker
No Limit Holdem Ring game
Blinds: $10/$20
5 players
Converter

Stack sizes:
UTG: $1649
CO: $2688
Button: $2471.50
SB: $2380
Hero: $1940

Pre-flop: (5 players) Hero is BB with J[img]/images/graemlins/diamond.gif[/img] A[img]/images/graemlins/spade.gif[/img]
UTG calls, CO calls, Button folds, SB calls, Hero checks.

Flop: A[img]/images/graemlins/diamond.gif[/img] J[img]/images/graemlins/club.gif[/img] K[img]/images/graemlins/spade.gif[/img] ($80, 4 players)
<font color="#cc0000">SB bets $80</font>, Hero calls, UTG calls, CO folds.

Turn: 4[img]/images/graemlins/spade.gif[/img] ($320, 3 players)
<font color="#cc0000">SB bets $250</font>, Hero calls, UTG calls.

River: 8[img]/images/graemlins/diamond.gif[/img] ($1070, 3 players)
SB checks, Hero checks, <font color="#cc0000">UTG bets $1000</font>, SB calls, Hero folds.