diff --git a/lib/ansible/modules/cloud/amazon/s3_bucket.py b/lib/ansible/modules/cloud/amazon/s3_bucket.py
index d530d836b3..814a8a5eb4 100644
--- a/lib/ansible/modules/cloud/amazon/s3_bucket.py
+++ b/lib/ansible/modules/cloud/amazon/s3_bucket.py
@@ -393,6 +393,11 @@ def main():
 
     flavour = 'aws'
 
+    # bucket names with .'s in them need to use the calling_format option,
+    # otherwise the connection will fail. See https://github.com/boto/boto/issues/2836
+    # for more details.
+    aws_connect_params['calling_format'] = OrdinaryCallingFormat()
+
     # Look at s3_url and tweak connection settings
     # if connecting to Walrus or fakes3
     try:
@@ -402,7 +407,6 @@ def main():
                 host=ceph.hostname,
                 port=ceph.port,
                 is_secure=ceph.scheme == 'https',
-                calling_format=OrdinaryCallingFormat(),
                 **aws_connect_params
             )
             flavour = 'ceph'
@@ -412,14 +416,14 @@ def main():
                 is_secure=fakes3.scheme == 'fakes3s',
                 host=fakes3.hostname,
                 port=fakes3.port,
-                calling_format=OrdinaryCallingFormat(),
                 **aws_connect_params
             )
         elif is_walrus(s3_url):
+            del aws_connect_params['calling_format']
             walrus = urlparse.urlparse(s3_url).hostname
             connection = boto.connect_walrus(walrus, **aws_connect_params)
         else:
-            connection = boto.s3.connect_to_region(location, is_secure=True, calling_format=OrdinaryCallingFormat(), **aws_connect_params)
+            connection = boto.s3.connect_to_region(location, is_secure=True, **aws_connect_params)
             # use this as fallback because connect_to_region seems to fail in boto + non 'classic' aws accounts in some cases
             if connection is None:
                 connection = boto.connect_s3(**aws_connect_params)