diff --git a/Lib/test/test_urllibnet.py b/Lib/test/test_urllibnet.py
index f324be9896a..c2388b8054d 100644
--- a/Lib/test/test_urllibnet.py
+++ b/Lib/test/test_urllibnet.py
@@ -8,6 +8,7 @@ import urllib.request
 import sys
 import os
 import email.message
+import time
 
 
 def _open_with_retry(func, host, *args, **kwargs):
@@ -180,6 +181,16 @@ class urlretrieveNetworkTests(unittest.TestCase):
         self.assertIsInstance(header, email.message.Message,
                               "header is not an instance of email.message.Message")
 
+    def test_data_header(self):
+        logo = "http://www.python.org/community/logos/python-logo-master-v3-TM.png"
+        file_location, fileheaders = self.urlretrieve(logo)
+        os.unlink(file_location)
+        datevalue = fileheaders.get('Date')
+        dateformat = '%a, %d %b %Y %H:%M:%S GMT'
+        try:
+            time.strptime(datevalue, dateformat)
+        except ValueError:
+            self.fail('Date value not in %r format', dateformat)
 
 
 def test_main():
diff --git a/Lib/urllib/request.py b/Lib/urllib/request.py
index ee819c3336b..ff871f9d9ad 100644
--- a/Lib/urllib/request.py
+++ b/Lib/urllib/request.py
@@ -1779,7 +1779,7 @@ class URLopener:
         else:
             encoding = ''
         msg = []
-        msg.append('Date: %s'%time.strftime('%a, %d %b %Y %T GMT',
+        msg.append('Date: %s'%time.strftime('%a, %d %b %Y %H:%M:%S GMT',
                                             time.gmtime(time.time())))
         msg.append('Content-type: %s' % type)
         if encoding == 'base64':