Classes and multiple .as files

programming flash
1

Hi

I got several classes, each in it’s own .as file, for better code organization.
I want one of the class to be able to access properties and methods of another class’ instance.
So here’s my document class (ob.as)

package
{
	import flash.display.MovieClip;
	
	public class ob extends MovieClip
	{
		public static var ad:SYSTEM;
		public static var da:PhysicsRenderer;
		
		public function ob():void
		{
			ad = new SYSTEM();
			da = new PhysicsRenderer();
		}
	}
}

SYSTEM.as:

package
{
	public class SYSTEM 
	{
		public function SYSTEM():void
		{
			trace("SYSTEM constructor");
		}
		public static function lol():void
		{
			trace("lol()");
		}
	}
}

PhysicsRenderer.as:

package
{
	public class PhysicsRenderer
	{
		
		public function PhysicsRenderer():void
		{
			ob.ad.lol();
		}
	}
}

On the PhysicsRenderer class, it seems I can actually access the instance (i.e. tracing ob.ad actually outputs something), but the lol() method doesn’t work. Neither does any properties, if I add them.

Has anyone else encountered this problem, or perhaps know a solution to this?
Thanks in Advance, Max