Dragging nested symbols

I've been trying to create a function that will allow me to drag and drop different images nested within symbols.

The code on theimage looks like this:

sym.getComposition().getStage().dragDrop("anti-virus");

The function I put on the top stage's CompositionReady event.

sym.dragDrop = function(item) {

  sym.$(item).draggable({ opacity: 0.35, revert: "invalid" });

  sym.$("SoftwareBox").droppable({ accept: sym.$(item) });

}

This doesn't work though.  The "anti-virus" image is within a symbol called "hardwaresoftware" which is in turn within a symbol called "article02".

Does anyone know what I've done wrong.  If I write the drag code directly in the image it works fine, i've tried doing an exact path to the image, symbol by symbol but that doesn't seem to work.  I used an alert to make sure the dragDrop function is running and it is.

Any help would be hugely appreciated.

Thanks