Flash 8.
stroke.shapeFill
Property; a Fill object that represents the fill settings of the stroke.
The following example specifies fill settings and then applies them to the stroke:
var fill = fl.getDocumentDOM().getCustomFill();
fill.linearGradient = true;
fill.colorArray = [ 00ff00, ff0000, fffff ];
var stroke = fl.getDocumentDOM().getCustomStroke();
stroke.shapeFill = fill;
fl.getDocumentDOM().setCustomStroke(stroke);