Add layer to group

Hi, I'm trying to add a layer to a group (this is a simple part of a much larger script), but can't seem to get it to work. Here is the script:

myDoc = app.activeDocument;
var newLayerSet = myDoc.layerSets.add();  
var myLayer = myDoc.layers[0];
myLayer.move(newLayerSet, ElementPlacement.INSIDE); 

Any idea why this doesn't work?

S