Minimum rotation increment?

Does anyone know if AS3 or FP9/10 enforces a minimum increment or resolution for the Sprite rotation property?

It seems to only allow rotations in multiples of 0.25 degrees.

For example:
var lines:Array = new Array();
for (i=0; i<2000; i++){
lines* = new Shape();
lines*.graphics.lineStyle(.1, 0x000000);
lines*.graphics.moveTo(0,0);
lines*.graphics.lineTo(700,0);
addChild(lines*);
lines*.y = 100;
lines*.rotation = i* .001;
}

This draws the lines in groups at 0.25 degree spacing with gaps between them.

Any thoughts?

Thanks!