rem: try { var mapiRegistry = Components.classes[ "@mozilla.org/mapiregistry;1" ]. getService( Components.interfaces.nsIMapiRegistry ); 
add: var mapiRegistry; try { var mapiRegistryProgID = "@mozilla.org/mapiregistry;1" if (mapiRegistryProgID in Components.classes) { mapiRegistry = Components.classes[mapiRegistryProgID].getService(Components.interfaces.nsIMapiRegistry); } else { mapiRegistry = null; } 
context: function showMailIntegrationDialog() {      try {        var mapiRegistry = Components.classes[ "@mozilla.org/mapiregistry;1" ].                       getService( Components.interfaces.nsIMapiRegistry );    }    catch (ex) {         mapiRegistry = null;    }    // showDialog is TRUE only if we did not bring up this dialog already    // and we are not the default mail client    var prefLocked = false;    if (mapiRegistry && mapiRegistry.showDialog) {        const prefbase = "system.windows.lock_ui.";        try {            prefService = Components.classes["@mozilla.org/preferences-service;1"]                          .getService()                          .QueryInterface(Components.interfaces.nsIPrefService);            prefBranch = prefService.getBranch(prefbase);                    if (prefBranch && prefBranch.prefIsLocked("defaultMailClient")) {                prefLocked = true;                if (prefBranch.getBoolPref("defaultMailClient"))                    mapiRegistry.setDefaultMailClient();                else                    mapiRegistry.unsetDefaultMailClient();            }        }        catch (ex) {}        if (!prefLocked && !mapiRegistry.isDefaultMailClient)            mapiRegistry.showMailIntegrationDialog();    }}
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/501a13fb8dc22b1f694553e7a29880a19bbb8d1e/accountUtils.js/buggy/mailnews/base/prefs/resources/content/accountUtils.js