Scrolling movieClip: Loop within set area?

[gparis]

function travel(me) {
    
        me.onEnterFrame = function() {
            me._x > 0 ? me._x -= 2 : me._x = 864;
            
        };
    
}
travel(blue);

blue.onRollOver = function() {
delete this.onEnterFrame;
};


blue.onRollOut = function(){
    travel(this);
}; 

functions are useful.

gparis