[Wolf]

здесь я получаю нормальное значение.

package {
 
	import flash.display.MovieClip;
	import flash.display.Sprite;
 
	public class Main extends Sprite {
		var flashVars:Object = stage.loaderInfo.parameters as Object;
 
		public function Main() {
			trace("Start");
			var s:Server=new Server();
			s.getData('getAccount','id','62810564');
			trace(s.resp.DATA.characters); //вот здесь нуль
			//var Acc:Account=new Account();
 
		}
	}
 
}

package
{
	//import vk.api.serialization.json;
	import flash.net.URLLoader;
	import flash.net.URLRequest;
	import flash.net.URLVariables;
	import flash.net.URLRequestMethod;
	import flash.events.Event;
	import vk.api.serialization.json.*;
	public class Server
	{
		private static const url:String = 'http://pira.ru/api.php';
		private static const skey:String = '812c0598112c692ab9e7dc2af0674cc3';
		private var loader:URLLoader;
		private var request:URLRequest;
		public var resp:Object;
 
		public function Server()
		{
			loader=new URLLoader();
			loader.addEventListener(Event.COMPLETE, onComplete);
		}
 
		public function getData(...params)
		{
			request = new URLRequest(url);
			request.method = URLRequestMethod.POST;
			var vars:URLVariables = new URLVariables();
			if (params[0])
			{
				vars['do'] = params[0];
			}
 
			if (params.length > 1 && params.length % 2 == 1)
			{
				for (var i=1; i<params.length; i++)
				{
					if (i % 2 == 1)
					{
						vars[params[i]] = params[i + 1];
					}
				}
			}
			vars['skey'] = skey;
			request.data = vars;
			loader.load(request);
trace(loader.data); //здесь тоже
		}
 
		public function onComplete(e:Event)
		{
			var js=new JSON()
			trace(loader.data);
			this.resp=js.decode(loader.data);
			trace(resp.DATA.characters[1]);
		}
 
	}
 
}