diff --git a/avatar/util.py b/avatar/util.py
index 4a63e30..c4f6021 100644
--- a/avatar/util.py
+++ b/avatar/util.py
@@ -8,6 +8,9 @@ def get_default_avatar_url():
     base_url = getattr(settings, 'STATIC_URL', None)
     if not base_url:
         base_url = getattr(settings, 'MEDIA_URL', '')
+    # Don't use base_url if the default avatar url starts with http:// 
+    if AVATAR_DEFAULT_URL.startswith('http://'):
+        return AVATAR_DEFAULT_URL
     # We'll be nice and make sure there are no duplicated forward slashes
     ends = base_url.endswith('/')
     begins = AVATAR_DEFAULT_URL.startswith('/')
@@ -34,4 +37,4 @@ def get_primary_avatar(user, size=80):
     if avatar:
         if not avatar.thumbnail_exists(size):
             avatar.create_thumbnail(size)
-    return avatar
\ No newline at end of file
+    return avatar