diff --git a/django/contrib/admin/sites.py b/django/contrib/admin/sites.py
index a48381d9063..6cb0c217954 100644
--- a/django/contrib/admin/sites.py
+++ b/django/contrib/admin/sites.py
@@ -1,6 +1,7 @@
 from django import http, template
 from django.contrib.admin import ModelAdmin
 from django.contrib.auth import authenticate, login
+from django.core.exceptions import ImproperlyConfigured
 from django.db.models.base import ModelBase
 from django.shortcuts import render_to_response
 from django.utils.safestring import mark_safe
@@ -66,19 +67,33 @@ class AdminSite(object):
 
         If a model is already registered, this will raise AlreadyRegistered.
         """
-        do_validate = admin_class and settings.DEBUG
-        if do_validate:
-            # don't import the humongous validation code unless required
+        # Don't import the humongous validation code unless required
+        if admin_class and settings.DEBUG:
             from django.contrib.admin.validation import validate
-        admin_class = admin_class or ModelAdmin
-        # TODO: Handle options
+        else:
+            validate = lambda model, adminclass: None
+
+        if not admin_class:
+            admin_class = ModelAdmin
         if isinstance(model_or_iterable, ModelBase):
             model_or_iterable = [model_or_iterable]
         for model in model_or_iterable:
             if model in self._registry:
                 raise AlreadyRegistered('The model %s is already registered' % model.__name__)
-            if do_validate:
-                validate(admin_class, model)
+
+            # If we got **options then dynamically construct a subclass of
+            # admin_class with those **options.
+            if options:
+                # For reasons I don't quite understand, without a __module__
+                # the created class appears to "live" in the wrong place,
+                # which causes issues later on.
+                options['__module__'] = __name__
+                admin_class = type("%sAdmin" % model.__name__, (admin_class,), options)
+
+            # Validate (which might be a no-op)
+            validate(admin_class, model)
+
+            # Instantiate the admin class to save in the registry
             self._registry[model] = admin_class(model, self)
 
     def unregister(self, model_or_iterable):
diff --git a/tests/regressiontests/admin_registration/__init__.py b/tests/regressiontests/admin_registration/__init__.py
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/tests/regressiontests/admin_registration/models.py b/tests/regressiontests/admin_registration/models.py
new file mode 100644
index 00000000000..fdfa3691b88
--- /dev/null
+++ b/tests/regressiontests/admin_registration/models.py
@@ -0,0 +1,64 @@
+"""
+Tests for various ways of registering models with the admin site.
+"""
+
+from django.db import models
+from django.contrib import admin
+
+class Person(models.Model):
+    name = models.CharField(max_length=200)
+
+class Place(models.Model):
+    name = models.CharField(max_length=200)
+
+__test__ = {'API_TESTS':"""
+
+
+# Bare registration
+>>> site = admin.AdminSite()
+>>> site.register(Person)
+>>> site._registry[Person]
+<django.contrib.admin.options.ModelAdmin object at ...>
+
+# Registration with a ModelAdmin
+>>> site = admin.AdminSite()
+>>> class NameAdmin(admin.ModelAdmin):
+...     list_display = ['name']
+...     save_on_top = True
+
+>>> site.register(Person, NameAdmin)
+>>> site._registry[Person]
+<regressiontests.admin_registration.models.NameAdmin object at ...>
+
+# You can't register the same model twice
+>>> site.register(Person)
+Traceback (most recent call last):
+    ...
+AlreadyRegistered: The model Person is already registered
+
+# Registration using **options
+>>> site = admin.AdminSite()
+>>> site.register(Person, search_fields=['name'])
+>>> site._registry[Person].search_fields
+['name']
+
+# With both admin_class and **options the **options override the fields in
+# the admin class.
+>>> site = admin.AdminSite()
+>>> site.register(Person, NameAdmin, search_fields=["name"], list_display=['__str__'])
+>>> site._registry[Person].search_fields
+['name']
+>>> site._registry[Person].list_display
+['__str__']
+>>> site._registry[Person].save_on_top
+True
+
+# You can also register iterables instead of single classes -- a nice shortcut
+>>> site = admin.AdminSite()
+>>> site.register([Person, Place], search_fields=['name'])
+>>> site._registry[Person]
+<django.contrib.admin.sites.PersonAdmin object at ...>
+>>> site._registry[Place]
+<django.contrib.admin.sites.PlaceAdmin object at ...>
+
+"""}