Line segment overlap, no more transparency

1

[FONT=Arial]Hi everyone![/FONT]
[FONT=Arial][/FONT]
[FONT=Arial]I have a rather simple actionscript 3 problem, but still couldn’t find any help myself.[/FONT]
[FONT=Arial]I’m trying to render line segments with graphics.moveTo and graphics.lineTo.[/FONT]
[FONT=Arial]The problem arise when two segments overlap. The transparency (alpha) seems to be added. I undestand that most people wants flash to do this, but what can I do if I don’t?[/FONT]
[FONT=Arial][/FONT]
[FONT=Arial]I would like all the line segments to have exactly the same transparency, even if they overlap. As if they were only one graphic element. (Is it possible to “merge” all graphics?)[/FONT]
[FONT=Arial][/FONT]
[FONT=Arial]Here a simple illustration of my attempt so far:[/FONT]

package
{
 import flash.display.Sprite; 
 public class Main extends Sprite
 {
  private var mySprite:Sprite;
  
  public function Main():void
  {
   this.mySprite = new Sprite();
   
   this.mySprite.graphics.lineStyle(20,0x00FF00,1.0);
   this.mySprite.graphics.moveTo(0,0);
   this.mySprite.graphics.lineTo(100,100);
   this.mySprite.graphics.moveTo(100,0);
   this.mySprite.graphics.lineTo(0,100);
   
   this.mySprite.alpha = 0.5;   
   addChild(this.mySprite);  
  }
 }
}

[FONT=Arial][/FONT]
[FONT=Arial]As you can see I’ve already tried to change not the alpha value of the lineStyle, but of the Sprite containing the graphics. Didn’t change anything.[/FONT]
[FONT=Arial][/FONT]
[FONT=Arial]Thanks in advance for your help. And if the task is too easy. Tell me how to have a border around all the lines (without crossings) ;-)[/FONT]