Call insane overbet on river with underfull?

[stealyourface]

NL 50 - 10 handed

Hero - $48
BB - $52.75

Preflop: Hero is UTG+1 with 8[img]/images/graemlins/heart.gif[/img], 8[img]/images/graemlins/club.gif[/img].
I call. MP2 calls. BB checks.

Flop: 9[img]/images/graemlins/diamond.gif[/img], 7[img]/images/graemlins/spade.gif[/img], 5[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(3 players)</font>
BB checks, Hero bets $1.25 MP2 folds. BB calls.

Turn: 8[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
BB checks. Hero bets $4. BB raises to $8. Hero calls $4.

River: 9[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
BB goes all-in for 44. Hero... ???

I dunno what the [censored] is going on... is this an easy call?

No reads on BB as it was his first hand at the table.