Script not working! I NEED HELP FAST!

Watch the swf and download the fla below. The 1st button makes the ball move to the right…the second button moves the ball to the left with this script on the 1st frame:

[color=blue]function Balltween() {[/color]
[color=blue]easeType = mx.transitions.easing.Strong.easeOut;[/color]
[color=blue]var begin = 41;[/color]
[color=blue]var end = 150;[/color]
[color=blue]var time = 3;[/color]
[color=blue]var mc = ball;[/color]
[color=blue]ballTween = new mx.transitions.Tween(mc, “_x”, easeType, begin, end, time, true);[/color]
[color=blue]}[/color]
[color=blue]function Balltween2() {[/color]
[color=blue]easeType = mx.transitions.easing.Strong.easeOut;[/color]
[color=blue]var begin = 150;[/color]
[color=blue]var end = 41;[/color]
[color=blue]var time = 3;[/color]
[color=blue]var mc = ball;[/color]
[color=blue]ballTween = new mx.transitions.Tween(mc, “_x”, easeType, begin, end, time, true);[/color]
[color=blue]}[/color]
[color=blue]myButton_btn.onRelease = function() {[/color]
[color=blue]Balltween();[/color]
[color=blue]}[/color]
[color=blue]myButton_btn2.onRelease = function() {[/color]
[color=blue]Balltween2();[/color]
[color=blue]}[/color]

[color=black]The problem is:
After clicking the 1st button…the Ball moves to _x = 150. If I click the second button it moves back to _x = 41. When I click the second button I dont want it to move Ball back to 41 unless it is sitting at 150. [/color]

So i tried doing something like this with the second button:

[color=blue]if(ball._x > 41){
myButton_btn2.onRelease = function() {
Balltween2();
}
}[/color]

[color=black]But it isn’t working.
I need help so bad otherwise I will be working all night on this. Any help is very appreciated!![/color]