($24) AKo missed vs. a donkish limp-caller. Call a push?

[Pocketbear]

The villain is a donk.

Full Tilt Poker
No Limit Holdem Tournament
Blinds: t30/t60
9 players
Converter

Stack sizes:
UTG: t2485
UTG+1: t1470
MP1: t1085
Hero: t1420
MP3: t1680
CO: t1275
Button: t1400
SB: t1245
BB: t1440

Pre-flop: (9 players) Hero is MP2 with A[img]/images/graemlins/heart.gif[/img] K[img]/images/graemlins/club.gif[/img]
2 folds, MP1 calls t60 <font color="aaaaaa">(pot was t90)</font>, <font color="#cc0000">Hero raises to t240</font>, 5 folds, MP1 calls t180 <font color="aaaaaa">(pot was t390)</font>.

Flop: 6[img]/images/graemlins/club.gif[/img] 2[img]/images/graemlins/heart.gif[/img] 4[img]/images/graemlins/club.gif[/img] (t570, 2 players)
<font color="#cc0000">MP1 is all-in t845</font>, Hero?