diff --git a/.travis.yml b/.travis.yml
index 05d3f83..6f3dc0f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,7 +2,11 @@ language: python
 python:
   - 2.6
   - 2.7
-# command to install dependencies, e.g. pip install -r requirements.txt --use-mirrors
-install: pip install -r requirements.txt
-# command to run tests, e.g. python setup.py test
+env:
+  - DJANGO_VERSION=1.3.4
+  - DJANGO_VERSION=1.4.2
+  - DJANGO_VERSION=1.5a1
+install:
+  - pip install -e git+git://github.com/django/django.git@${DJANGO_VERSION}#egg=django
+  - pip install -r requirements.txt --use-mirrors
 script: fab test
diff --git a/django_browserid/auth.py b/django_browserid/auth.py
index b9a6afb..583dda5 100644
--- a/django_browserid/auth.py
+++ b/django_browserid/auth.py
@@ -17,10 +17,12 @@
 
 try:
     from django.contrib.auth import get_user_model
-    User = get_user_model()
 except ImportError:
     from django.contrib.auth.models import User
 
+    def get_user_model(*args, **kwargs):
+        return User
+
 
 log = logging.getLogger(__name__)
 
@@ -45,6 +47,14 @@ class BrowserIDBackend(object):
     supports_inactive_user = True
     supports_object_permissions = False
 
+    def __init__(self):
+        """
+        Store the current user model on creation to avoid issues if
+        settings.AUTH_USER_MODEL changes, which usually only happens during
+        tests.
+        """
+        self.User = get_user_model()
+
     def verify(self, *args):
         warn('Deprecated, please use the standalone function '
              'django_browserid.verify instead.', DeprecationWarning)
@@ -52,7 +62,7 @@ def verify(self, *args):
 
     def filter_users_by_email(self, email):
         """Return all users matching the specified email."""
-        return User.objects.filter(email=email)
+        return self.User.objects.filter(email=email)
 
     def create_user(self, email):
         """Return object for a newly created user account."""
@@ -62,7 +72,7 @@ def create_user(self, email):
         else:
             username = default_username_algo(email)
 
-        return User.objects.create_user(username, email)
+        return self.User.objects.create_user(username, email)
 
     def authenticate(self, assertion=None, audience=None):
         """``django.contrib.auth`` compatible authentication method.
@@ -86,7 +96,8 @@ def authenticate(self, assertion=None, audience=None):
         # log and bail. randomly selecting one seems really wrong.
         users = self.filter_users_by_email(email=email)
         if len(users) > 1:
-            log.warn('{0} users with email address {1}.'.format(len(users), email))
+            log.warn('{0} users with email address {1}.'.format(len(users),
+                                                                email))
             return None
         if len(users) == 1:
             return users[0]
@@ -107,8 +118,8 @@ def authenticate(self, assertion=None, audience=None):
 
     def get_user(self, user_id):
         try:
-            return User.objects.get(pk=user_id)
-        except User.DoesNotExist:
+            return self.User.objects.get(pk=user_id)
+        except self.User.DoesNotExist:
             return None
 
     def _load_module(self, path):
diff --git a/django_browserid/tests/models.py b/django_browserid/tests/models.py
new file mode 100644
index 0000000..70ecbbb
--- /dev/null
+++ b/django_browserid/tests/models.py
@@ -0,0 +1,23 @@
+"""
+This Source Code Form is subject to the terms of the Mozilla Public
+License, v. 2.0. If a copy of the MPL was not distributed with this
+file, You can obtain one at http://mozilla.org/MPL/2.0/.
+"""
+from django.db import models
+
+try:
+    from django.contrib.auth.models import AbstractBaseUser
+except ImportError:
+    AbstractBaseUser = object
+
+
+class CustomUser(AbstractBaseUser):
+    USERNAME_FIELD = 'email'
+
+    email = models.EmailField(unique=True, db_index=True)
+
+    def get_full_name(self):
+        return self.email
+
+    def get_short_name(self):
+        return self.email
diff --git a/django_browserid/tests/settings.py b/django_browserid/tests/settings.py
index 2b30b24..a4cb642 100644
--- a/django_browserid/tests/settings.py
+++ b/django_browserid/tests/settings.py
@@ -5,6 +5,8 @@
 """
 TEST_RUNNER = 'django_nose.runner.NoseTestSuiteRunner'
 
+SECRET_KEY = 'asdf'
+
 DATABASES = {
     'default': {
         'NAME': 'test.db',
@@ -15,6 +17,7 @@
 INSTALLED_APPS = (
     'django_nose',
     'django_browserid',
+    'django_browserid.tests',
 
     'django.contrib.auth',
     'django.contrib.contenttypes',
diff --git a/django_browserid/tests/test_auth.py b/django_browserid/tests/test_auth.py
index 803f787..463e22a 100644
--- a/django_browserid/tests/test_auth.py
+++ b/django_browserid/tests/test_auth.py
@@ -12,6 +12,12 @@
 from django_browserid.auth import BrowserIDBackend, default_username_algo
 from django_browserid.tests import mock_browserid
 
+try:
+    from django.contrib.auth import get_user_model
+    from django_browserid.tests.models import CustomUser
+except ImportError:
+    get_user_model = False
+
 
 def new_user(email, username=None):
         """Creates a user with the specified email for testing."""
@@ -87,3 +93,36 @@ def test_user_created_signal(self, user_created):
         # created.
         user = self.auth('a@b.com')
         assert user_created.call.called_with(user=user)
+
+
+# Only run custom user model tests if we're using a version of Django that
+# supports it.
+if get_user_model:
+    @patch.object(settings, 'AUTH_USER_MODEL', 'tests.CustomUser')
+    class CustomUserModelTests(TestCase):
+        def _auth(self, backend=None, verified_email=None):
+            if backend is None:
+                backend = BrowserIDBackend()
+
+            with mock_browserid(verified_email):
+                return backend.authenticate(assertion='asdf', audience='asdf')
+
+        def test_existing_user(self):
+            """If a custom user exists with the given email, return them."""
+            user = CustomUser.objects.create(email='a@test.com')
+            authed_user = self._auth(verified_email='a@test.com')
+            assert user == authed_user
+
+        @patch.object(settings, 'BROWSERID_CREATE_USER', True)
+        def test_create_new_user(self):
+            """
+            If a custom user does not exist with the given email, create a new
+            user and return them.
+            """
+            class CustomUserBrowserIDBackend(BrowserIDBackend):
+                def create_user(self, email):
+                    return CustomUser.objects.create(email=email)
+            user = self._auth(backend=CustomUserBrowserIDBackend(),
+                              verified_email='b@test.com')
+            assert isinstance(user, CustomUser)
+            assert user.email == 'b@test.com'
diff --git a/docs/details/advanced.rst b/docs/details/advanced.rst
index 5517e90..1ec27d0 100644
--- a/docs/details/advanced.rst
+++ b/docs/details/advanced.rst
@@ -128,3 +128,13 @@ Signals
 
     * **sender**: The function that created the user instance.
     * **user**: The user instance that was created.
+
+
+Custom User Model
+-----------------
+
+Django 1.5 allows you to specify a custom model to use in place of the built-in
+User model with the ``AUTH_USER_MODEL`` setting. ``django-browserid`` supports
+custom User models, however you will most likely need to subclass
+``django-browserid.BrowserIDBackend`` and override the ``create_user``,
+``get_user``, and ``filter_users_by_email`` functions to work with your class.