What steps will reproduce the problem?
1. Run the JanRain.OpenID.ConsumerPortal web site project in the source 
tree.
2. Enter a valid OpenID and click Login.
3. Within your OpenID Provider, click Cancel.
4. Again, enter your same valid OpenID and click Login.
5. Continue through your OpenID Provider to complete login.
** Login still fails **

What is the expected output? What do you see instead?
Login should succeed on the second attempt.

Part of what's going wrong here is that the openid.mode parameter in the 
querystring is being persisted across requests, so instead of being a 
simple "cancel" or "id_res", it's concatenated as a comma-delimited 
array: "cancel,id_res".  GenericConsumer.cs:64 is not equipped to handle 
this, as it counts on just a simple string being there.
But the bug may be that we send the openid.mode back to the Provider 
between attempts in the first place.

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