How to display a menubar of darwin?

Hello.

I develop an platform independent GUI application using the xulrunner 1.9.1.
the GUI is written in XUL codes.
menuber of MacOSX version of the application is not displayed.
Linux and Window version, its menuber is successfully  displayed.
Some one please suggest what is wrong.

The following (1) is a XUL file example of in the problem.
Does something need such an activation when switching windows....?

Thank you
Hirohisa Mori.

-----------------------------------
(1)
<?xml version="1.0" encoding="utf-8"?>
<?xml-stylesheet href="chrome://global/skin/" type="text/css"?>
<!DOCTYPE window SYSTEM "chrome://lettuce/locale/LyMainWindow.dtd">

<!-- ========================================================================================= -->
<!-- XUL GUI declaration for LyMainWindow                                                      -->
<!-- http://www.globalbase.org/                                                                -->
<!-- ========================================================================================= -->

<window 
		xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
		id="WINDOW_MAIN"
		title="MainWindow"
		hidden="false"
		gtWindowType="LyMainWindow"
		onload="onLoad()"

		width="200"
		height="100"
		>
	
	<!-- ===================================================================================== -->
	<!-- read ly scripts																	   -->
	<!-- ===================================================================================== -->

.......

    <!-- ===================================================================================== -->
	<!-- keyset																				-->
	<!-- ===================================================================================== -->
	<keyset id="keyset">
	</keyset>
	
	<!-- ===================================================================================== -->
	<!-- menu																				  -->
	<!-- ===================================================================================== -->

	<menubar id="MENUBAR">
        <menu label="File" id="MENU_FILE">
			<menupopup id="MENUPOPUP_FILE">
                <menuitem id="MENUITEM_NEW_PROJECT" 
					label="&menu.newProject;"
					gtType="menuAppGlobal"
					gtFieldType="GT:CREATE"
					gtCreate='"createLyWindow",
						"chrome://lettuce/content/ly/itp/xulrunner/lettuce/src/LyProjectWindow.xul",
						"ProjectWindow$",
						{"parameters":{"DRAW_PANE":{"project":"off"}}}'
				/>
                <menuitem id="MENUITEM_GT_TEST_WINDOW"
                   label="OpenGtTestWindow"
                   gtType="menuAppGlobal"
                   gtFieldType="GT:CREATE"
                   gtCreate='"createLyWindow",
						"chrome://lettuce/content/ly/itp/xulrunner/lettuce/src/LyGtTestWindow.xul",
						"GtTestWindow$"'
				/>
                <menuitem id="MENUITEM_BASIC_SETTING" 
					label="basic settings"
					gtType="menuAppGlobal"
					gtFieldType="GT:CREATE"
					gtCreate='"createLyWindow",
						"chrome://lettuce/content/ly/itp/xulrunner/lettuce/src/LyBasicSettingDialog.xul",
						"BasicSettingWindow"'
				/>
			</menupopup>
        </menu>
	</menubar>

    <box>			
        <label value="This window is the main window." />
    </box>
</window>