Multiple MCs as buttons

programming flash
1

I have created a MC that acts like a button (rollover, rollout states). However when i try to add more to the frame they don’t want to work:
This is the AS for one button:

this.button1.onRollOver = function(){
	button1.gotoAndPlay("_over");
}
this.button1.onRollOut = function(){
	button1.gotoAndPlay("_out");
}

And when I add a second I just use the same but change the instance names to suit the second MC.

this.button1.onRollOver = function(){
	button1.gotoAndPlay("_over");
}
this.button1.onRollOut = function(){
	button1.gotoAndPlay("_out");
}

this.button2.onRollOver = function(){
	button2.gotoAndPlay("_over");
}
this.button2.onRollOut = function(){
	button2.gotoAndPlay("_out");
}

Any ideas what I am doing wrong? This is really bugging me!