<menupopup id="fvd_single_tools_popup_menu" onpopupshowing="return fvd_single.tools_menu_showing(event)">
                    <menuitem id="fvd_single_js_enabled" type="checkbox" autocheck="false" label="&txt.tools_popup.javascript.title;" oncommand="alert(1)" />
                    <menuitem label="&txt.tools_popup.check_ip.title;" oncommand="" />
                    <menuitem label="&txt.tools_popup.speed_test.title;" oncommand="" />
                    <menuitem label="&txt.tools_popup.whois.title;" oncommand="" />
                </menupopup>

this.tools_menu_showing = function(event)
    {
        try
        {
            var val = Components.classes['@mozilla.org/preferences-service;1'].getService(Components.interfaces.nsIPrefBranch).getBoolPref('javascript.enabled');
            var it = document.getElementById('fvd_single_js_enabled');
            if (it != null)
            {
                if (val == true)
                {
                    it.setAttribute('checked', 'true');
                } else
                {
                    it.removeAttribute('checked');
                }
            }

        } catch (e) {}


        alert(document.getElementById('fvd_single_js_enabled').getAttribute('checked'));

        return true;
    };