How do you play against this

On Party Poker. Unbelievable really. It's the 82nd hand and I've barely raised a pot. Does this guy really think I'm bluffing.

PL Texas Hold'em $6 Buy-in Trny:27934712 Level:6 Blinds(300/600) - Sunday, August 27, 15:54:05 ET 2006
Table Table 114067 (Real Money)
Seat 6 is the button
Total number of players : 3
Seat 5: RumTiddle ( $5222 )
Seat 6: lilbitaluck ( $5784 )
Seat 7: DBLAUGHTSPY ( $8994 )
Trny:27934712 Level:6
Blinds(300/600)
** Dealing down cards **
Dealt to RumTiddle [ Kc As ]
lilbitaluck folds.
DBLAUGHTSPY raises [900].
RumTiddle raises [3000].
DBLAUGHTSPY calls [2400].
** Dealing Flop ** [ 4s, Td, 3s ]
DBLAUGHTSPY bets [600].
RumTiddle is all-In [1622]
DBLAUGHTSPY calls [1022].
** Dealing Turn ** [ 5s ]
** Dealing River ** [ 8d ]
DBLAUGHTSPY shows [ 5h, Ks ] a pair of fives.
RumTiddle shows [ Kc, As ] high card ace.
DBLAUGHTSPY wins 10444 chips from the main pot with a pair of fives.
RumTiddle finished in third place and won $10.