Why wont this script work?!

programming flash
1

I am trying to create a menu system that has several buttons flying out. I have put the following script on my buttons and it just wont work, I cant understand why not. I am using Flash 8, as2 and a flash 8 player

onClipEvent(load){
tx=100;
ty=100;
k=.2;
damp=.9;
}
onClipEvent(enterFrame){
if(!drag){
ax=(tx-_x)k;
ay=(ty-_y)k;
vx+=ax;
vy+=ay;
vx=damp;
vy=damp;
_x+=vx;
_y+=vy;
}
}