diff --git a/tempest/tests/test_authorization.py b/tempest/tests/test_authorization.py
index ae7fd3f..29f6155 100644
--- a/tempest/tests/test_authorization.py
+++ b/tempest/tests/test_authorization.py
@@ -7,7 +7,7 @@
 from tempest.services.nova.json.images_client import ImagesClient
 from tempest.services.nova.json.servers_client import ServersClient
 from tempest.common.utils.data_utils import rand_name
-from tempest.exceptions import NotFound, ComputeFault, BadRequest, Unauthorized
+from tempest import exceptions
 from tempest.tests import utils
 
 
@@ -35,33 +35,37 @@
             and cls.user2_password != None
             and cls.user2_tenant_name != None):
 
-            # Setup a client instance for the second user
-            cls.multi_user = True
+            try:
+                # Setup a client instance for the second user
+                auth_url = cls.config.identity.auth_url
 
-            auth_url = cls.config.identity.auth_url
-
-            if cls.config.identity.strategy == 'keystone':
-                client_args = (cls.config, cls.user2, cls.user2_password,
-                               auth_url, cls.user2_tenant_name)
+                if cls.config.identity.strategy == 'keystone':
+                    cls.client_args = (cls.config, cls.user2,
+                                       cls.user2_password,
+                                       auth_url, cls.user2_tenant_name)
+                else:
+                    cls.client_args = (cls.config, cls.user2,
+                                       cls.user2_password, auth_url)
+                cls.other_client = ServersClient(*cls.client_args)
+                cls.other_images_client = ImagesClient(*cls.client_args)
+            except exceptions.AuthenticationFailure:
+                # multi_user is already set to false, just fall through
+                pass
             else:
-                client_args = (cls.config, cls.user2, cls.user2_password,
-                               auth_url)
+                cls.multi_user = True
 
-            cls.other_client = ServersClient(*client_args)
-            cls.other_images_client = ImagesClient(*client_args)
+                name = rand_name('server')
+                resp, server = cls.client.create_server(name, cls.image_ref,
+                                                        cls.flavor_ref)
+                cls.client.wait_for_server_status(server['id'], 'ACTIVE')
+                resp, cls.server = cls.client.get_server(server['id'])
 
-            name = rand_name('server')
-            resp, server = cls.client.create_server(name, cls.image_ref,
-                                                    cls.flavor_ref)
-            cls.client.wait_for_server_status(server['id'], 'ACTIVE')
-            resp, cls.server = cls.client.get_server(server['id'])
-
-            name = rand_name('image')
-            resp, body = cls.client.create_image(server['id'], name)
-            image_id = cls._parse_image_id(resp['location'])
-            cls.images_client.wait_for_image_resp_code(image_id, 200)
-            cls.images_client.wait_for_image_status(image_id, 'ACTIVE')
-            resp, cls.image = cls.images_client.get_image(image_id)
+                name = rand_name('image')
+                resp, body = cls.client.create_image(server['id'], name)
+                image_id = cls._parse_image_id(resp['location'])
+                cls.images_client.wait_for_image_resp_code(image_id, 200)
+                cls.images_client.wait_for_image_status(image_id, 'ACTIVE')
+                resp, cls.image = cls.images_client.get_image(image_id)
 
     @classmethod
     def tearDownClass(cls):
@@ -69,35 +73,35 @@
             cls.client.delete_server(cls.server['id'])
             cls.images_client.delete_image(cls.image['id'])
 
-    @raises(NotFound)
+    @raises(exceptions.NotFound)
     @attr(type='negative')
     @utils.skip_unless_attr('multi_user', 'Second user not configured')
     def test_get_server_for_other_account_fails(self):
         """A GET request for a server on another user's account should fail"""
         self.other_client.get_server(self.server['id'])
 
-    @raises(NotFound)
+    @raises(exceptions.NotFound)
     @attr(type='negative')
     @utils.skip_unless_attr('multi_user', 'Second user not configured')
     def test_delete_server_for_other_account_fails(self):
         """A DELETE request for another user's server should fail"""
         self.other_client.delete_server(self.server['id'])
 
-    @raises(ComputeFault)
+    @raises(exceptions.NotFound)
     @attr(type='negative')
     @utils.skip_unless_attr('multi_user', 'Second user not configured')
     def test_update_server_for_other_account_fails(self):
         """An update server request for another user's server should fail"""
         self.other_client.update_server(self.server['id'], name='test')
 
-    @raises(NotFound)
+    @raises(exceptions.NotFound)
     @attr(type='negative')
     @utils.skip_unless_attr('multi_user', 'Second user not configured')
     def test_list_server_addresses_for_other_account_fails(self):
         """A list addresses request for another user's server should fail"""
         self.other_client.list_addresses(self.server['id'])
 
-    @raises(NotFound)
+    @raises(exceptions.NotFound)
     @attr(type='negative')
     @utils.skip_unless_attr('multi_user', 'Second user not configured')
     def test_list_server_addresses_by_network_for_other_account_fails(self):
@@ -107,42 +111,42 @@
         server_id = self.server['id']
         self.other_client.list_addresses_by_network(server_id, 'public')
 
-    @raises(NotFound)
+    @raises(exceptions.NotFound)
     @attr(type='negative')
     @utils.skip_unless_attr('multi_user', 'Second user not configured')
     def test_change_password_for_other_account_fails(self):
         """A change password request for another user's server should fail"""
         self.other_client.change_password(self.server['id'], 'newpass')
 
-    @raises(NotFound)
+    @raises(exceptions.NotFound)
     @attr(type='negative')
     @utils.skip_unless_attr('multi_user', 'Second user not configured')
     def test_reboot_server_for_other_account_fails(self):
         """A reboot request for another user's server should fail"""
         self.other_client.reboot(self.server['id'], 'HARD')
 
-    @raises(NotFound)
+    @raises(exceptions.NotFound)
     @attr(type='negative')
     @utils.skip_unless_attr('multi_user', 'Second user not configured')
     def test_rebuild_server_for_other_account_fails(self):
         """A rebuild request for another user's server should fail"""
         self.other_client.rebuild(self.server['id'], self.image_ref_alt)
 
-    @raises(NotFound)
+    @raises(exceptions.NotFound)
     @attr(type='negative')
     @utils.skip_unless_attr('multi_user', 'Second user not configured')
     def test_resize_server_for_other_account_fails(self):
         """A resize request for another user's server should fail"""
         self.other_client.resize(self.server['id'], self.flavor_ref_alt)
 
-    @raises(NotFound)
+    @raises(exceptions.NotFound)
     @attr(type='negative')
     @utils.skip_unless_attr('multi_user', 'Second user not configured')
     def test_create_image_for_other_account_fails(self):
         """A create image request for another user's server should fail"""
         self.other_images_client.create_image(self.server['id'], 'testImage')
 
-    @raises(BadRequest)
+    @raises(exceptions.BadRequest)
     @attr(type='negative')
     @utils.skip_unless_attr('multi_user', 'Second user not configured')
     def test_create_server_with_unauthorized_image(self):
@@ -150,7 +154,7 @@
         self.other_client.create_server('test', self.image['id'],
                                          self.flavor_ref)
 
-    @raises(Unauthorized)
+    @raises(exceptions.BadRequest)
     @attr(type='negative')
     @utils.skip_unless_attr('multi_user', 'Second user not configured')
     def test_create_server_fails_when_tenant_incorrect(self):
@@ -158,10 +162,11 @@
         A create server request should fail if the tenant id does not match
         the current user
         """
-        os_other = openstack.Manager(self.user2, self.user2_password,
-                                     self.user2_tenant_name)
-        os_other.servers_client.client.base_url = self.client.client.base_url
-        os_other.servers_client.create_server('test', self.image['id'],
+        other_servers_client = ServersClient(*self.client_args)
+
+        # Change the base URL to impersonate another user
+        other_servers_client.client.base_url = self.client.client.base_url
+        other_servers_client.create_server('test', self.image['id'],
                                               self.flavor_ref)
 
     @classmethod