Crouch animation when key pressed ....

Sorry I will try it here because I have posted the same
question in the getting started forum. I was searching
the hole forum with the word animation to find some
information about my problem, but I didn't found a good
code snippet which can bring me to the right way. All
I want is that the player can crouch if I press a
defined key. All I get working is that:

function serverCmdDuck(%client)
{
%client.player.setActionThread(head);
echo("playing my animation");
}

moveMap.bindCmd(keyboard, "b", "commandToServer('Duck');","" );

The amazing thing is, that if I want to play the 'land'
animation which is definitely in the animation files,
it doesn't work. Also I not sure if this is the right
way to play a own animation. Sorry I'm new to torque
so I have a lot of questions.