diff --git a/greenmine/base/fixtures/initial_user.json b/greenmine/base/fixtures/initial_user.json
index 2142710a..7b1e0cac 100644
--- a/greenmine/base/fixtures/initial_user.json
+++ b/greenmine/base/fixtures/initial_user.json
@@ -7,14 +7,14 @@
         "first_name": "", 
         "last_name": "", 
         "description": "", 
-        "default_language": null, 
+        "default_language": "", 
         "color": "", 
         "photo": "", 
         "is_active": true, 
         "colorize_tags": false, 
-        "default_timezone": null, 
+        "default_timezone": "", 
         "is_superuser": true, 
-        "token": null, 
+        "token": "", 
         "is_staff": true, 
         "last_login": "2013-04-04T07:36:09.880Z", 
         "groups": [], 
diff --git a/greenmine/scrum/management/commands/sample_data.py b/greenmine/scrum/management/commands/sample_data.py
index d2ee11f3..3c84087c 100644
--- a/greenmine/scrum/management/commands/sample_data.py
+++ b/greenmine/scrum/management/commands/sample_data.py
@@ -34,6 +34,7 @@ class Command(BaseCommand):
             username='user%d' % (counter),
             first_name='user%d' % (counter),
             email='foouser%d@domain.com' % (counter),
+            token=''.join(random.sample('abcdef0123456789', 10)),
         )
 
         user.set_password('user%d' % (counter))