Overcalling an all-in bet with a small pair

[Blarg]

Here's a small pair I had when my stack was starting to dwindle a bit. I was still competitive with most of the field, but two others were far ahead. I had a pair, but was it worth risking the tournament here to come into the pot when there was already someone calling the all-in? It looks like calling would commit all my chips to the pot.

This hand seems more complicated to me than it appears at first glance, since I'm fighting the all-in for half the pot and the guy who called him for the other half. I could beat, or lose to, either or both, winning or losing the full pot or all of it.

Party Poker No-Limit Hold'em Tourney, Big Blind is t50 (6 handed) converter

MP (t1970)
CO (t445)
Button (t3160)
Hero (t545)
BB (t1545)
UTG (t335)

Preflop: Hero is SB with 6[img]/images/graemlins/diamond.gif[/img], 6[img]/images/graemlins/club.gif[/img].
<font color="#666666">2 folds</font>, Button calls t335, <font color="#666666">2 folds</font>.

Flop: (t410) 6[img]/images/graemlins/spade.gif[/img], 7[img]/images/graemlins/spade.gif[/img], 5[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>

Turn: (t410) J[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>

River: (t410) J[img]/images/graemlins/diamond.gif[/img]