[mooncar]

var my_btn =  this[cities[i] + '_dist'][cities[i] + '_btn'];
my_btn.myCity = cities[i];
my_btn.onRelease = function() {
   trace(this.myCity) //выводит  Prim и Berd, так?
   trace(marker_mc); //не undefined , виден?
   marker_mc.gotoAndStop(this.myCity); //должен работать тогда
};