Zombie Pigmen Anger = Lag+Server Crash

Hello,

The bug I'm describing has been in the last 3 snapshots from what i can tell and causes the server to crash, when zombie pigmen become angry the world starts to lag and eventually causes the server to crash from overload, i checked this in single player and it also gets the lag.
Before the server crashes however you will get lag to the point where the zombies do not move they just kind of blink about to their destination, even falling zombie pigment will freeze mid air for a little while.

I checked with the server members and they also get this.

Thanks,
Night