[FMX] scope of variables in loop?

[binlid]

var x:Number = 0;
var y:Number = 0;
var i:Number = 1;

while(y < 400)
{
  while(x < 600)
  {
	this.attachMovie("hover_mc", "sq_", this.getNextHighestDepth(), {_x:x, _y:y});
	x += 50;
	i++;
  }
  y += 50;
}

i have no access to y in the (x < 600) loop… yet i gets incremented every loop… i am baffled! can anybody shed any light on this?