attachMovie problem

Hi, for some reason the attachMovie in this piece of code just refuses to run

theListener.onLoadInit = function(loadedMc:MovieClip) {
var dropShadow:DropShadowFilter = new DropShadowFilter(0, 45, 0xFFFFFF, 100, 2, 2, 255, 1);
loadedMc.filters = [dropShadow];
loadedMc.createEmptyMovieClip("mc_picover", 2);
trace(loadedMc.mc_picover.attachMovie("mc_picover", "mc_over", 1));
loadedMc.mc_picover._alpha = 0;
loadedMc.mc_picover._width = _root.mc_slide.mc_slideshow["pic"+thePic]._width - 2;
loadedMc.mc_picover._x = 1;
loadedMc.mc_picover._y = 1;
loadedMc.onRollOver = function() {
var overTween:Tween = new Tween(loadedMc.mc_picover, "_alpha", None.easeIn, loadedMc.mc_picover._alpha, 100, 1, true);
};
loadedMc.onRollOut = function() {
var overTween:Tween = new Tween(loadedMc.mc_picover, "_alpha", None.easeIn, loadedMc.mc_picover._alpha, 0, 1, true);
};

if (thePic < theArray.length-1) {
thePic++
loadPic(thePic);
}
};

function loadPic(id:Number) {
var newClip:MovieClip = _root.mc_slide.mc_slideshow.createEmptyMovieClip("pic"+id, id);
newClip._y = 30;
newClip._x = 13;
newClip._x += _root.mc_slide.mc_slideshow["pic"+(id-1)]._width + _root.mc_slide.mc_slideshow["pic"+(id-1)]._x;
theImage.loadClip(theArray[id][1], newClip);
};


everything else works (bar the stuff trying to reference the attached movie), any ideas? the trace just returns "undefined".

i've checked the export for as box and the linkage is all correct, i can use the same peice of code to attach it to any other movie (dynamically created or not) but the movie i actually want to attach it to wont accept it