How to dynamically create AS3 Object properties?

It works for me:

var _someArray:Array = ["one","two", new Sprite()]
			var obj:Object = {};
			for (var i:int = 0; i < _someArray.length; i++) {
			   obj[("someProperty" + i)] = _someArray[i];
			}
			for (var name:String in obj) {
				trace("loop init -> "+ name + " -> " + obj[name] )
			}
			// then I want to read those the same way for example
			for(i = 0; i < _someArray.length; i++){
			   trace(obj[("someProperty" + i)]);
			}

Traces:

loop init -> someProperty0 -> one
loop init -> someProperty1 -> two
loop init -> someProperty2 -> [object Sprite]
one
two
[object Sprite]