$100r wierd spot with KK

[djk123]

utg is mikeymer and other dude is Premier. Thoughts on preflop? Betting the flop seems standard, but then all hell breaks loose. Is this an easy fold?

Poker Stars
No Limit Holdem Tournament
Blinds: t150/t300
(Ante: t25)
9 players
Converter

Stack sizes:
UTG: t7150
UTG+1: t6081
MP1: t12525
MP2: t7595
MP3: t6450
CO: t15180
djk123: t15523
SB: t19797
BB: t3430

Pre-flop: (9 players) djk123 is Button with K[img]/images/graemlins/diamond.gif[/img] K[img]/images/graemlins/spade.gif[/img]
<font color="#cc0000">UTG raises to t800</font>, 5 folds, djk123 calls t800 <font color="aaaaaa">(pot was t1475)</font>, SB calls t650 <font color="aaaaaa">(pot was t2275)</font>, BB folds.

Flop: 5[img]/images/graemlins/heart.gif[/img] 3[img]/images/graemlins/club.gif[/img] 4[img]/images/graemlins/club.gif[/img] (t2925, 3 players)
SB checks, UTG checks, <font color="#cc0000">djk123 bets t1800</font>, <font color="#cc0000">SB raises to t5000</font>, <font color="#cc0000">UTG raises all-in t6325</font>, djk123