NL25 straight in limped pot

[HarmMan]

I have some difficulties playing limped pots. Would you play this different on any street? What range do you put villain on?
I haven't played many hands with vaillain but he seems fishy: 41/13/2.1 over 50 hands.

Full Tilt Poker, $0.10/$0.25 NL Hold'em Cash Game, 3 Players
LeggoPoker (http://www.leggopoker.com)Hand History Converter (http://www.leggopoker.com/hh)

Hero (BTN): $30.30
SB: $25
BB: $50.60

Pre-Flop: 8/images/graemlins/heart.gif 7/images/graemlins/spade.gif dealt to Hero (BTN)
SB folds, BB calls $0.15, Hero checks

Flop: ($0.50) K/images/graemlins/heart.gif 6/images/graemlins/heart.gif 5/images/graemlins/heart.gif (2 Players)
<font color="red">BB bets $0.25</font>, Hero calls $0.25

Turn: ($1) 3/images/graemlins/diamond.gif (2 Players)
<font color="red">BB bets $0.25</font>, Hero calls $0.25

River: ($1.50) 9/images/graemlins/spade.gif (2 Players)
<font color="red">BB bets $0.50</font>, <font color="red">Hero raises to $3</font>, <font color="red">BB raises to $6</font>, Hero...

[VLV]

I would just call. I don't think any worse hand is calling another raise from you, plus this is a very possible line for a flopped flush for such a fisshy player.

Edit: Just gotta also say that I would have raised this flop.