I figured this guy was on a flush draw and was trying to bluff the turn, and given that he couldn't even call $7 more on the river, I'm pretty sure I was right.
PokerStars Game #1631706444: Hold'em No Limit ($0.25/$0.50) - 2005/05/03 - 18:03:53 (ET)
Table 'Alnilam' Seat #6 is the button
Seat 1: GRIMBO ($49.50 in chips)
Seat 2: Hilmer ($47.75 in chips)
Seat 3: RichZany1 ($45.25 in chips)
Seat 4: MetsFan340 ($3.75 in chips)
Seat 5: JLizard ($49.75 in chips)
Seat 6: dsaxton ($27.15 in chips)
Seat 7: ThreeOfive ($66.85 in chips)
Seat 8: deezerk ($50 in chips)
Seat 9: mechan1c ($35.15 in chips)
ThreeOfive: posts small blind $0.25
deezerk: posts big blind $0.50
*** HOLE CARDS ***
Dealt to dsaxton [4c 5c]
mechan1c: folds
GRIMBO: calls $0.50
Hilmer: folds
RichZany1: folds
MetsFan340: folds
JLizard: folds
dsaxton: raises $1.50 to $2
ThreeOfive: folds
deezerk: folds
GRIMBO: calls $1.50
*** FLOP *** [6c 9h 2h]
GRIMBO: checks
dsaxton: bets $4
GRIMBO: calls $4
*** TURN *** [6c 9h 2h] [6s]
GRIMBO: bets $5
dsaxton: raises $9 to $14
GRIMBO: calls $9
*** RIVER *** [6c 9h 2h 6s] [Js]
GRIMBO: checks
dsaxton: bets $7.15 and is all-in
GRIMBO: folds
dsaxton collected $38.75 from pot
dsaxton: shows [4c 5c] (a pair of Sixes)
*** SUMMARY ***
Total pot $40.75 | Rake $2
Board [6c 9h 2h 6s Js]
Seat 1: GRIMBO folded on the River
Seat 2: Hilmer folded before Flop (didn't bet)
Seat 3: RichZany1 folded before Flop (didn't bet)
Seat 4: MetsFan340 folded before Flop (didn't bet)
Seat 5: JLizard folded before Flop (didn't bet)
Seat 6: dsaxton (button) collected ($38.75)
Seat 7: ThreeOfive (small blind) folded before Flop
Seat 8: deezerk (big blind) folded before Flop
Seat 9: mechan1c folded before Flop (didn't bet)