diff --git a/nova/auth/manager.py b/nova/auth/manager.py
index c5ff348d..98d5f6eb 100644
--- a/nova/auth/manager.py
+++ b/nova/auth/manager.py
@@ -310,7 +310,8 @@ class AuthManager(object):
             LOG.debug('signature: %s', signature)
             if signature != expected_signature:
                 LOG.audit(_("Invalid signature for user %s"), user.name)
-                raise exception.NotAuthorized(_('Signature does not match'))
+                raise exception.InvalidSignature(signature=signature,
+                                                 user=user)
         elif check_type == 'ec2':
             # NOTE(vish): hmac can't handle unicode, so encode ensures that
             #             secret isn't unicode
@@ -321,7 +322,8 @@ class AuthManager(object):
             LOG.debug('signature: %s', signature)
             if signature != expected_signature:
                 LOG.audit(_("Invalid signature for user %s"), user.name)
-                raise exception.NotAuthorized(_('Signature does not match'))
+                raise exception.InvalidSignature(signature=signature,
+                                                 user=user)
         return (user, project)
 
     def get_access_key(self, user, project):
diff --git a/nova/tests/test_instance_types.py b/nova/tests/test_instance_types.py
index dd7d0737..ef271518 100644
--- a/nova/tests/test_instance_types.py
+++ b/nova/tests/test_instance_types.py
@@ -75,13 +75,13 @@ class InstanceTypeTestCase(test.TestCase):
     def test_invalid_create_args_should_fail(self):
         """Ensures that instance type creation fails with invalid args"""
         self.assertRaises(
-                exception.InvalidInputException,
+                exception.InvalidInput,
                 instance_types.create, self.name, 0, 1, 120, self.flavorid)
         self.assertRaises(
-                exception.InvalidInputException,
+                exception.InvalidInput,
                 instance_types.create, self.name, 256, -1, 120, self.flavorid)
         self.assertRaises(
-                exception.InvalidInputException,
+                exception.InvalidInput,
                 instance_types.create, self.name, 256, 1, "aa", self.flavorid)
 
     def test_non_existant_inst_type_shouldnt_delete(self):
diff --git a/nova/tests/test_scheduler.py b/nova/tests/test_scheduler.py
index efd12f93..968ef9d6 100644
--- a/nova/tests/test_scheduler.py
+++ b/nova/tests/test_scheduler.py
@@ -768,14 +768,10 @@ class SimpleDriverTestCase(test.TestCase):
         s_ref = self._create_compute_service(host='somewhere',
                                              memory_mb_used=12)
 
-        try:
-            self.scheduler.driver._live_migration_dest_check(self.context,
-                                                             i_ref,
-                                                             'somewhere')
-        except exception.NotEmpty, e:
-            c = (e.message.find('Unable to migrate') >= 0)
+        self.assertRaises(exception.MigrationError,
+                          self.scheduler.driver._live_migration_dest_check,
+                          self.context, i_ref, 'somewhere')
 
-        self.assertTrue(c)
         db.instance_destroy(self.context, instance_id)
         db.service_destroy(self.context, s_ref['id'])