Passing arguments to desktop app from browser

I'm trying to pass arguments to my desktop app using cutom URI schemes. I can get the app to open from the browser, but the invoke event never seems to be dispatched, hence, I can't get arguments to the app. I'm adding the event listener on the main classes constructor like so :

public function MyApp()

{

  NativeApplication.nativeApplication.addEventListener( InvokeEvent.INVOKE, onInvoke );

  NativeApplication.nativeApplication.addEventListener( BrowserInvokeEvent.BROWSER_INVOKE, onInvoke );

  super();

}

public function onInvoke(e:*):void

{

  // NEVER TRIGGERED

  ConfigConstants.WAS_INVOKED = true;

  ConfigConstants.INVOKE_PARAMS = ArrayUtil.copyArray(e.arguments);

}

My HTML link looks like this :

<a href="myapp.open://hello&world">click</a>

Any ideas ?