diff --git a/mozilla/embedding/components/windowwatcher/src/nsPrompt.cpp b/mozilla/embedding/components/windowwatcher/src/nsPrompt.cpp
index 562e84f9ba9..8f632132914 100644
--- a/mozilla/embedding/components/windowwatcher/src/nsPrompt.cpp
+++ b/mozilla/embedding/components/windowwatcher/src/nsPrompt.cpp
@@ -80,8 +80,21 @@ NS_NewPrompter(nsIPrompt **result, nsIDOMWindow *aParent)
 nsresult
 NS_NewAuthPrompter(nsIAuthPrompt **result, nsIDOMWindow *aParent)
 {
-
   nsresult rv;
+  nsCOMPtr<nsIPromptFactory> factory =
+    do_GetService(NS_PWMGR_AUTHPROMPTFACTORY);
+  if (factory) {
+    // We just delegate everything to the pw mgr if we can
+    rv = factory->GetPrompt(aParent,
+                            NS_GET_IID(nsIAuthPrompt),
+                            reinterpret_cast<void**>(result));
+    // If the password manager doesn't support the interface, fall back to the
+    // old way of doing things. This will allow older apps that haven't updated
+    // to work still.
+    if (rv != NS_NOINTERFACE)
+      return rv;
+  }
+
   *result = 0;
 
   nsPrompt *prompter = new nsPrompt(aParent);
diff --git a/mozilla/embedding/tests/unit/test_wwauthpromptfactory.js b/mozilla/embedding/tests/unit/test_wwauthpromptfactory.js
new file mode 100644
index 00000000000..aba2cf684f6
--- /dev/null
+++ b/mozilla/embedding/tests/unit/test_wwauthpromptfactory.js
@@ -0,0 +1,67 @@
+const Cc = Components.classes;
+const Ci = Components.interfaces;
+
+var authPromptRequestReceived;
+
+const tPFCID = Components.ID("{749e62f4-60ae-4569-a8a2-de78b649660f}");
+const tPFContract = "@mozilla.org/passwordmanager/authpromptfactory;1";
+
+/*
+ * TestPromptFactory
+ *
+ * Implements nsIPromptFactory
+ */
+var TestPromptFactory = {
+  QueryInterface: function tPF_qi(iid) {
+    if (iid.equals(Ci.nsISupports) ||
+        iid.equals(Ci.nsIFactory) ||
+        iid.equals(Ci.nsIPromptFactory))
+      return this;
+    throw Components.results.NS_ERROR_NO_INTERFACE;
+  },
+
+  createInstance: function tPF_ci(outer, iid) {
+    if (outer)
+      throw Components.results.NS_ERROR_NO_AGGREGATION;
+    return this.QueryInterface(iid);
+  },
+
+  lockFactory: function tPF_lockf(lock) {
+    throw Components.results.NS_ERROR_NOT_IMPLEMENTED;
+  },
+
+  getPrompt : function tPF_getPrompt(aWindow, aIID) {
+    if (aIID.equals(Ci.nsIAuthPrompt) ||
+        aIID.equals(Ci.nsIAuthPrompt2)) {
+      authPromptRequestReceived = true;
+      return {};
+    }
+
+    throw Components.results.NS_ERROR_NO_INTERFACE;
+  }
+}; // end of TestPromptFactory implementation
+
+/*
+ * The tests
+ */
+function run_test() {
+  Components.manager.nsIComponentRegistrar.registerFactory(tPFCID,
+    "TestPromptFactory", tPFContract, TestPromptFactory);
+
+  // Make sure that getting both nsIAuthPrompt and nsIAuthPrompt2 works
+  // (these should work independently of whether the application has
+  // nsIPromptService2)
+  var ww = Cc["@mozilla.org/embedcomp/window-watcher;1"].getService();
+
+  authPromptRequestReceived = false;
+
+  do_check_neq(ww.nsIPromptFactory.getPrompt(null, Ci.nsIAuthPrompt), null);
+
+  do_check_true(authPromptRequestReceived);
+
+  authPromptRequestReceived = false;
+
+  do_check_neq(ww.nsIPromptFactory.getPrompt(null, Ci.nsIAuthPrompt2), null);
+
+  do_check_true(authPromptRequestReceived);
+}