I have a map where you can dynamically add graphics to and when you do so and then zoom in or out the simpleFillSymbol always goes to the top of the graphics layer.
if i pan the map far and then come back to the location of the graphics they redraw correctly. I have tried adding an onExtentChange handler and calling map.graphics.redraw and map.setExtent(map.extent) in order to replicate the redraw when the pan occurs but I am not getting the same results.
Have you made sure the autoMoveGraphicsToTop property of your GraphicsLayer is set to false?