Array.slice is not working

programming flash
1

Array.slice is not working

var a:Array = []

for (var i:int = 0; i<2; i++){
	a* = [];
	//b* = [];
	
	for (var j:int = 0; j<2; j++)
	{
		a*[j] = {type1:j};
	}
}

var b:Array = a.slice();

trace(a[1][1].type1); // 1
trace(b[1][1].type1); // 1

b[1][1].type1 = 2;

[COLOR="Red"]trace(a[1][1].type1); // 2[/COLOR]
trace(b[1][1].type1); // 2