diff --git a/services/sync/modules/engines/clients.js b/services/sync/modules/engines/clients.js
index d39d628e9a05..30d0d5068412 100644
--- a/services/sync/modules/engines/clients.js
+++ b/services/sync/modules/engines/clients.js
@@ -96,7 +96,7 @@ ClientStore.prototype = {
   },
 
   _ClientStore_init: function ClientStore__init() {
-    this.__proto__.__proto__._init.call(this);
+    this._init.call(this);
     this.clients = {};
     this.loadSnapshot();
   },
diff --git a/services/sync/modules/engines/tabs.js b/services/sync/modules/engines/tabs.js
index 25c22a17c23c..cb3c5afdb9f1 100644
--- a/services/sync/modules/engines/tabs.js
+++ b/services/sync/modules/engines/tabs.js
@@ -50,17 +50,17 @@ Cu.import("resource://weave/constants.js");
 
 Function.prototype.async = Async.sugar;
 
-function TabEngine(pbeId) {
-  this._init(pbeId);
+function TabEngine() {
+  this._init();
 }
-
 TabEngine.prototype = {
-  __proto__: new BlobEngine(),
-
-  get name() "tabs",
-  get displayName() { return "Tabs"; },
-  get logName() "TabEngine",
-  get serverPrefix() "user-data/tabs/",
+  __proto__: SyncEngine.prototype,
+  name: "tabs",
+  displayName: "Tabs",
+  logName: "Tabs",
+  _storeObj: TabStore,
+  _trackerObj: TabTracker,
+  _recordObj: ClientTabsRecord
 
   get virtualTabs() {
     let virtualTabs = {};
@@ -76,28 +76,15 @@ TabEngine.prototype = {
       }
     }
     return virtualTabs;
-  },
-
-  get _store() {
-    let store = new TabStore();
-    this.__defineGetter__("_store", function() store);
-    return this._store;
-  },
-
-  get _tracker() {
-    let tracker = new TabTracker(this);
-    this.__defineGetter__("_tracker", function() tracker);
-    return this._tracker;
   }
-
 };
 
 function TabStore() {
-  this._init();
+  this._TabStore_init();
 }
 TabStore.prototype = {
   __proto__: new Store(),
-  _logName: "TabStore",
+  _logName: "Tabs.Store",
 
   get _sessionStore() {
     let sessionStore = Cc["@mozilla.org/browser/sessionstore;1"].
diff --git a/services/sync/modules/service.js b/services/sync/modules/service.js
index a8f27c4e2916..a0e84d794b6f 100644
--- a/services/sync/modules/service.js
+++ b/services/sync/modules/service.js
@@ -474,10 +474,14 @@ WeaveSvc.prototype = {
 
       this._log.debug("Logging in user " + this.username);
 
-      yield this.verifyLogin(self.cb, this.username, this.password);
-
-      this._loggedIn = true;
-      self.done(true);
+      try {
+        yield this.verifyLogin(self.cb, this.username, this.password);
+        this._loggedIn = true;
+        self.done(true);
+      } catch (e) {
+        this._loggedIn = false;
+        self.done(false);
+      }
     };
     this._localLock(
       this._catchAll(