addWebBrowserListener crash

hello
i still not succeed to use JavaXPCOM in a embedded java application.

now, i try to have a webprogresslistener so i use addWebBrowserListener 
from nsIWebBrowser:

	nsIEventQueueService eventQueueServive = 
(nsIEventQueueService)serviceManager.getServiceByContractID("@mozilla.org/event-queue-service;1",nsIEventQueueService.NS_IEVENTQUEUESERVICE_IID);
	nsIEventQueue eventQueue = 
eventQueueServive.getSpecialEventQueue(nsIEventQueueService.UI_THREAD_EVENT_QUEUE);
	nsIProxyObjectManager proxy = 
(nsIProxyObjectManager)componentManager.createInstanceByContractID("@mozilla.org/xpcomproxy;1",null,nsIProxyObjectManager.NS_IPROXYOBJECTMANAGER_IID);
	nsIWebBrowser webBrowserProxy = 
(nsIWebBrowser)proxy.getProxyForObject(eventQueue,nsIWebBrowser.NS_IWEBBROWSER_IID,webBrowser,nsIProxyObjectManager.INVOKE_SYNC);

	    WebProgressListener webProgressListener = new WebProgressListener();
	webBrowserProxy.addWebBrowserListener(webProgressListener,
		  nsIWebProgressListener.NS_IWEBPROGRESSLISTENER_IID);

but the JVM crash:

Stack: [0xb155c000,0xb15dc000),  sp=0xb15da894,  free space=506k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, 
C=native code)
C  [libxul.so+0x1fed80]
C  [libxul.so+0x143f22]  _ZNK15nsQueryReferentclERK4nsIDPPv+0x32
C  [libxul.so+0x1421b9] 
_ZN13nsCOMPtr_base18assign_from_helperERK15nsCOMPtr_helperRK4nsID+0x19
C  [libxul.so+0x831670]
C  [libxul.so+0x1a26b9]  XPTC_InvokeByIndex+0x29
C  [libxul.so+0x18fe5b]
C  [libxul.so+0x189417]  PL_HandleEvent+0x27
C  [libxul.so+0x189729]  PL_ProcessPendingEvents+0x59
C  [libxul.so+0x18b5ae]
C  [libxul.so+0x999c05]
C  [libglib-2.0.so.0+0x54c7f]
C  [libglib-2.0.so.0+0x2b731]  g_main_context_dispatch+0x181
C  [libglib-2.0.so.0+0x2e7a6]
C  [libglib-2.0.so.0+0x2eb67]  g_main_loop_run+0x1b7
C  [libgtk-x11-2.0.so.0+0x129281]  gtk_main+0xc1
C  [libxul.so+0x99a052]
C  [libxul.so+0x1a26b9]  XPTC_InvokeByIndex+0x29
C  [libxul.so+0x1fb39e] 
Java_org_mozilla_xpcom_internal_XPCOMJavaProxy_callXPCOMMethod+0x13e
C  [libjavaxpcomglue.so+0x100c] 
Java_org_mozilla_xpcom_internal_XPCOMJavaProxy_callXPCOMMethod+0x3c
j 
org.mozilla.xpcom.internal.XPCOMJavaProxy.callXPCOMMethod(Ljava/lang/Object;Ljava/lang/String;[Ljava/lang/Object;)Ljava/lang/Object;+0
j 
org.mozilla.xpcom.internal.XPCOMJavaProxy.invoke(Ljava/lang/Object;Ljava/lang/reflect/Method;[Ljava/lang/Object;)Ljava/lang/Object;+214
j  $Proxy2.run()V+9
j  TestListenerGtk$WindowThread.run()V+439

any idea ?