Index: django/db/models/fields/__init__.py
===================================================================
--- django/db/models/fields/__init__.py	(révision 16859)
+++ django/db/models/fields/__init__.py	(copie de travail)
@@ -16,7 +16,6 @@
 from django.utils.text import capfirst
 from django.utils.translation import ugettext_lazy as _
 from django.utils.encoding import smart_unicode, force_unicode, smart_str
-from django.utils import datetime_safe
 from django.utils.ipv6 import clean_ipv6_address
 
 class NOT_PROVIDED:
@@ -669,7 +668,7 @@
         if val is None:
             data = ''
         else:
-            data = datetime_safe.new_date(val).strftime("%Y-%m-%d")
+            data = str(val)
         return data
 
     def formfield(self, **kwargs):
@@ -743,8 +742,7 @@
         if val is None:
             data = ''
         else:
-            d = datetime_safe.new_datetime(val)
-            data = d.strftime('%Y-%m-%d %H:%M:%S')
+            data = str(val.replace(microsecond=0, tzinfo=None))
         return data
 
     def formfield(self, **kwargs):
Index: django/db/backends/sqlite3/base.py
===================================================================
--- django/db/backends/sqlite3/base.py	(révision 16859)
+++ django/db/backends/sqlite3/base.py	(copie de travail)
@@ -320,15 +320,10 @@
             dt = dt - delta
     except (ValueError, TypeError):
         return None
+    # typecast_timestamp returns a date or a datetime without timezone.
+    # It will be formatted as "%Y-%m-%d" or "%Y-%m-%d %H:%M:%S[.%f]"
+    return str(dt)
 
-    if isinstance(dt, datetime.datetime):
-        rv = dt.strftime("%Y-%m-%d %H:%M:%S")
-        if dt.microsecond:
-            rv = "%s.%0.6d" % (rv, dt.microsecond)
-    else:
-        rv = dt.strftime("%Y-%m-%d")
-    return rv
-
 def _sqlite_regexp(re_pattern, re_string):
     try:
         return bool(re.search(re_pattern, re_string))
Index: django/db/backends/__init__.py
===================================================================
--- django/db/backends/__init__.py	(révision 16859)
+++ django/db/backends/__init__.py	(copie de travail)
@@ -9,7 +9,6 @@
 from django.db import DEFAULT_DB_ALIAS
 from django.db.backends import util
 from django.db.transaction import TransactionManagementError
-from django.utils import datetime_safe
 from django.utils.importlib import import_module
 
 
@@ -718,7 +717,7 @@
         """
         if value is None:
             return None
-        return datetime_safe.new_date(value).strftime('%Y-%m-%d')
+        return unicode(value)
 
     def value_to_db_datetime(self, value):
         """
@@ -731,7 +730,7 @@
 
     def value_to_db_time(self, value):
         """
-        Transform a datetime value to an object compatible with what is expected
+        Transform a time value to an object compatible with what is expected
         by the backend driver for time columns.
         """
         if value is None:
Index: django/contrib/sitemaps/tests/basic.py
===================================================================
--- django/contrib/sitemaps/tests/basic.py	(révision 16859)
+++ django/contrib/sitemaps/tests/basic.py	(copie de travail)
@@ -67,7 +67,7 @@
 <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
 <url><loc>%s/location/</loc><lastmod>%s</lastmod><changefreq>never</changefreq><priority>0.5</priority></url>
 </urlset>
-""" % (self.base_url, date.today().strftime('%Y-%m-%d')))
+""" % (self.base_url, date.today()))
 
     def test_simple_custom_sitemap(self):
         "A simple sitemap can be rendered with a custom template"
@@ -79,7 +79,7 @@
 <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
 <url><loc>%s/location/</loc><lastmod>%s</lastmod><changefreq>never</changefreq><priority>0.5</priority></url>
 </urlset>
-""" % (self.base_url, date.today().strftime('%Y-%m-%d')))
+""" % (self.base_url, date.today()))
 
     @skipUnless(settings.USE_I18N, "Internationalization is not enabled")
     def test_localized_priority(self):
@@ -93,7 +93,7 @@
         # haven't been rendered in localized format
         response = self.client.get('/simple/sitemap.xml')
         self.assertContains(response, '<priority>0.5</priority>')
-        self.assertContains(response, '<lastmod>%s</lastmod>' % date.today().strftime('%Y-%m-%d'))
+        self.assertContains(response, '<lastmod>%s</lastmod>' % date.today())
         deactivate()
 
     def test_generic_sitemap(self):
@@ -152,7 +152,7 @@
 <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
 <url><loc>http://testserver/location/</loc><lastmod>%s</lastmod><changefreq>never</changefreq><priority>0.5</priority></url>
 </urlset>
-""" % date.today().strftime('%Y-%m-%d'))
+""" % date.today())
 
     @skipUnless("django.contrib.sites" in settings.INSTALLED_APPS, "django.contrib.sites app not installed.")
     def test_sitemap_get_urls_no_site_1(self):
Index: django/contrib/admin/filters.py
===================================================================
--- django/contrib/admin/filters.py	(révision 16859)
+++ django/contrib/admin/filters.py	(copie de travail)
@@ -281,9 +281,9 @@
 
         today = datetime.date.today()
         one_week_ago = today - datetime.timedelta(days=7)
-        today_str = (isinstance(self.field, models.DateTimeField)
-                        and today.strftime('%Y-%m-%d 23:59:59')
-                        or today.strftime('%Y-%m-%d'))
+        today_str = str(today)
+        if isinstance(self.field, models.DateTimeField):
+            today_str += ' 23:59:59'
 
         self.lookup_kwarg_year = '%s__year' % self.field_path
         self.lookup_kwarg_month = '%s__month' % self.field_path
@@ -299,7 +299,7 @@
                 self.lookup_kwarg_day: str(today.day),
             }),
             (_('Past 7 days'), {
-                self.lookup_kwarg_past_7_days_gte: one_week_ago.strftime('%Y-%m-%d'),
+                self.lookup_kwarg_past_7_days_gte: str(one_week_ago),
                 self.lookup_kwarg_past_7_days_lte: today_str,
             }),
             (_('This month'), {
Index: tests/regressiontests/admin_filters/tests.py
===================================================================
--- tests/regressiontests/admin_filters/tests.py	(révision 16859)
+++ tests/regressiontests/admin_filters/tests.py	(copie de travail)
@@ -186,8 +186,8 @@
         self.assertEqual(choice['query_string'], '?date_registered__year=%s'
                                                 % (self.today.year))
 
-        request = self.request_factory.get('/', {'date_registered__gte': self.one_week_ago.strftime('%Y-%m-%d'),
-                                                 'date_registered__lte': self.today.strftime('%Y-%m-%d')})
+        request = self.request_factory.get('/', {'date_registered__gte': str(self.one_week_ago),
+                                                 'date_registered__lte': str(self.today)})
         changelist = self.get_changelist(request, Book, modeladmin)
 
         # Make sure the correct queryset is returned
@@ -201,7 +201,7 @@
         self.assertEqual(choice['selected'], True)
         self.assertEqual(choice['query_string'], '?date_registered__gte=%s'
                                                  '&date_registered__lte=%s'
-                                                % (self.one_week_ago.strftime('%Y-%m-%d'), self.today.strftime('%Y-%m-%d')))
+                                                % (str(self.one_week_ago), str(self.today)))
 
     def test_allvaluesfieldlistfilter(self):
         modeladmin = BookAdmin(Book, site)
