AppEngine AuthSub won't upgrade Token

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Implement authentication using AuthSub
2. Try to upgrade auth token into a session token
3. Get a UnableToUpgradeToken error right in your face.

It works when using the dev_appserver.py but it won't work once you upload it 
to appengine.

What is the expected output? What do you see instead?
The token should be upgraded and saved to the datastore. In fact that worked 
just fine before March 14th 2011.
I wonder if the new oauth2 implementation that was announced at the same time 
may have broken authsub on appengine.

Attached is the code I have and can be used to reproduce the error. 

Please use labels and text to provide additional information.
gauth authsub UnableToUpgradeToken

Original issue reported on code.google.com by eduardocereto on 16 Mar 2011 at 8:04

Attachments:

• login.py

[GoogleCodeExporter]

Hello,

Have you tried registering your domain? It seems to have resolved this issue 
for other people who used AuthSub authentication.

I hope this helped!
Best,
Alain

Original comment by ala...@google.com on 16 Mar 2011 at 8:06

[GoogleCodeExporter]

Have read the docs again and saw that as an option. Will try to do that and 
will comeback here. I wonder why it works fine for loopback

Original comment by eduardocereto on 16 Mar 2011 at 8:15