Starting Mozilla from XPCShell (revisited)

A while ago in a thread in this group the following code has been
suggested to start mozilla from xpcshell:

----------- 8<--------------- cut here ----------- 8< -------------

var EventQClass =
Components.classes['@mozilla.org/event-queue-service;1'];

var EventQObj	=  EventQClass.getService(Components.interfaces.nsIEventQueueService);

EventQObj.createThreadEventQueue();

var AppShellClass = 
Components.classes['@mozilla.org/appshell/appShellService;1'];
var AppShellObj = 
AppShellClass.getService(Components.interfaces.nsIAppShellService);

var URLClass =  Components.classes['@mozilla.org/network/standard-url;1'];
var URLObj = URLClass.createInstance(Components.interfaces.nsIURL);

URLObj.scheme="file";
URLObj.path="/tmp/test.xul";

AppShellObj.Initialize(null,null);


var test = new Object();
toto = AppShellObj.CreateTopLevelWindow(null,URLObj,
	true,true,
	Components.interfaces.nsIWebBrowserChrome.CHROME_ALL,
	640,480,test);

AppShellObj.Run();

----------- 8<--------------- cut here ----------- 8< -------------

It seemed to work for some people judging by discussion. However,
here is what i get with my freshly compiled mozilla-1.0

a) If i run the code as provided i get:

:uncaught exception: [Exception... "Component returned failure code:
0xc1f30001 (NS_ERROR_NOT_INITIALIZED) [nsIURL.scheme]"  nsresult:
"0xc1f30001 (NS_ERROR_NOT_INITIALIZED)"  location: "JS frame ::
/tmp/test.js :: <TOP_LEVEL> :: line 14"  data: no]

b) removing URLObj.scheme="file" gets me just a bit further:
TypeError: AppShellObj.Initialize is not a function

 Well, i can only assume that the provided interface to AppShell has
changed
or may be i need to use another object alltogether?
 
 In a nutshell, i will need to create an application here where i will
be able
to load and control mozilla from xpcshell using javascript or,
ideally, using
Python XPCOM (but that's for later).

Advice?