Small set getting action

[ERT]

Any advice on this one? Seems like he's got trips or maybe two pair. Do I call this?
No reads on BB.

Party Poker No-Limit Hold'em, $ BB (10 handed) converter

BB ($37.43)
UTG ($21)
UTG+1 ($42.23)
UTG+2 ($47.65)
Hero ($66.85)
MP2 ($56.45)
MP3 ($10.65)
CO ($52.65)
Button ($64.85)
SB ($51.07)

Preflop: Hero is MP1 with 4[img]/images/graemlins/diamond.gif[/img], 4[img]/images/graemlins/spade.gif[/img]. SB posts a blind of $0.25.
<font color="#666666">3 folds</font>, Hero calls $0.50, <font color="#666666">2 folds</font>, <font color="#CC3333">CO raises to $2</font>, <font color="#666666">2 folds</font>, BB calls $1.50, Hero calls $1.50.

Flop: ($6.25) K[img]/images/graemlins/club.gif[/img], J[img]/images/graemlins/heart.gif[/img], 4[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(3 players)</font>
BB checks, Hero checks, <font color="#CC3333">CO bets $5</font>, BB calls $5, <font color="#CC3333">Hero raises to $10</font>, CO folds, BB raises all-in $30.43, Hero?