N00b with another middle pair hand...

I have a total of 4200 hands, most at this level. I use PT and PokerAce, but the only player I have any history with at this table folds this hand preflop.

PokerStars 0.05/0.10 Hold'em (9 handed) converter

Preflop: pdxhero is MP3 with J[img]/images/graemlins/spade.gif[/img], 3[img]/images/graemlins/spade.gif[/img]. pdxhero posts a blind of $0.05.
<font color="#666666">1 fold</font>, UTG+1 calls, <font color="#666666">2 folds</font>, pdxhero (poster) checks, <font color="#666666">2 folds</font>, SB completes, BB checks.

Flop: (4 SB) 2[img]/images/graemlins/club.gif[/img], Q[img]/images/graemlins/spade.gif[/img], J[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(4 players)</font>
SB checks, <font color="#CC3333">BB bets</font>, UTG+1 calls, pdxhero ... ?

I have read SSHe example 5 on p.270. Does the backdoor flush possibility change things or is this a fold?