This hand occurred at a recent tournament. We're in the fourth or fifth level, blinds 200-400. I've been the tightest player at the table, haven't seen many cards and haven't yet won a pot. I have about 8,000 of my beginning 10,000 chips. I'm in middle position and get dealt JJ, by far the best hand I've seen in two hours of play. I open raise to 1,000. Player to my left, V1, who's short, goes all in for 3,500. Three players later, V2 (who I think was a blind, but not sure) raises to 6,000. (Chip totals are approximate.) He's a middle aged guy, has played some pots and seems decent; in other words, not a young crazy agro or the table captain. He has an above average stack but is not the chip leader. I'm not worried about V1, I know he's shoving with any pocket pair or broadway cards. But what about V2s 4-bet? What's he representing? Do I call (or raise), essentially, if not actually, committing my entire stack? Or fold? Your thoughts and analysis are appreciated.