Kill Particle on Collision MEL-Script not working

Maya
1

Hi everybody!

I am new in Maya and having trouble with following MEL script:

global proc ParticleCollisionBoneAndRotor (string $particleObject, int $particleId, string $geometryObject)
{

if(!`strcmp " DeathZone" $geometryObject`)
{
	print("nn**killing Particle**nn");

// delete cafeboneparticle.pt[$particleId];
// cafeboneparticle.dth;

}

};

This Function is always called each time a particle collides with something.
I want the cafebones to die everytime they collide with the rotor.
The console displays killing Particle but the kill of the particles does not work. if i write a select -af cafeboneparticle.pt[$particleId]; it works fine, but killing the particle does not work. What is wrong?? What do I have to do?
Hope somebody helps!

thank you , kalchas adabesi