rem: prefBranch = prefBranch.QueryInterface(Components.interfaces.nsIPrefBranchInternal); 
add: prefBranch = prefBranch.QueryInterface(Components.interfaces.nsIPrefBranch2); 
context: function utilityOnLoad(aEvent){  var broadcaster = document.getElementById("Communicator:WorkMode");  if (!broadcaster) return;  var observerService = Components.classes[kObserverServiceProgID]		          .getService(Components.interfaces.nsIObserverService);  observerService.addObserver(offlineObserver, "network:offline-status-changed", false);  // make sure we remove this observer later  var prefService = Components.classes["@mozilla.org/preferences-service;1"];  prefService = prefService.getService(Components.interfaces.nsIPrefService);  var prefBranch = prefService.getBranch(null);  prefBranch = prefBranch.QueryInterface(Components.interfaces.nsIPrefBranchInternal);  prefBranch.addObserver("network.proxy.type", proxyTypeObserver, false);  addEventListener("unload", utilityOnUnload, false);  // set the initial state  var ioService = Components.classes[kIOServiceProgID]		      .getService(Components.interfaces.nsIIOService);  setOfflineUI(ioService.offline);}
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/331d73b7095bb826fff93981e5f30f40f21c0df7/utilityOverlay.js/clean/suite/common/utilityOverlay.js