diff --git a/requests/defaults.py b/requests/defaults.py
index 951c056d..770001f9 100644
--- a/requests/defaults.py
+++ b/requests/defaults.py
@@ -26,6 +26,7 @@ defaults = dict()
 defaults['base_headers'] = {
     'User-Agent': 'python-requests/%s' % __version__,
     'Accept-Encoding': ', '.join(('identity', 'deflate', 'compress', 'gzip')),
+    'Accept': '*/*'
 }
 
 defaults['proxies'] = {}