Поковырялся, разобрался, придумал.
Вот, если кому понадобится:

Код AS3:
package {
import flash.display.Sprite;
import flash.net.LocalConnection;
import flash.text.TextField;
import fl.controls.Button;
import flash.text.TextFieldAutoSize;
import flash.events.MouseEvent;
public class Main extends Sprite {
private var count:int = 0;
private var connectionName:String = "myConnection";
private var localConnectionSender:LocalConnection = new LocalConnection();
private var localConnectionReceiver:LocalConnection = new LocalConnection();
private var slaveConnectionsIDS:Array = [];
public function Main() {
localConnectionReceiver.client = this;
connectReceiver();
if( count > 0 ) {
localConnectionSender.send( connectionName + "0", "slaveInit", count );
} else {
var button:Button = new Button();
button.label = "send";
button.addEventListener( MouseEvent.CLICK, sendMessage );
addChild( button );
}
}
private function connectReceiver():void {
try {
localConnectionReceiver.connect( connectionName + count.toString() );
} catch( error:Error ) {
count++;
connectReceiver();
}
}
private function sendMessage( event:MouseEvent ):void {
for( var i:int = 0; i < slaveConnectionsIDS.length; i++ ) {
localConnectionSender.send( connectionName + slaveConnectionsIDS[ i ], "messageFromMaster", "myMessage" );
}
}
public function slaveInit( slaveCount:int ):void {
trace( count, "init:", slaveCount );
slaveConnectionsIDS.push( slaveCount );
}
public function messageFromMaster( message:String ):void {
var tf:TextField = new TextField();
tf.text = "message from master swf: " + message;
tf.autoSize = TextFieldAutoSize.LEFT;
addChild( tf );
}
}
}
Прикрепляю исходники.
Объяснять сейчас влом, если надо, пишите, расскажу.