OAuth or authsub?

[Calarinda]

Two questions; 1) Should I use OAuth 2.0? 2) Am I using the right "registration" since it doesn't work on my Google Sites URL?

Here's what the Google Finance Dev guide says:

This link... http://code.google.com/apis/finance/docs/2.0/developers_guide_protocol.html#Authenticating

...states: "A client must authenticate before using the Finance Data API. It can authenticate using either of two approaches: AuthSub proxy authentication or ClientLogin username/password authentication." For more information about authentication with the Google Data Protocol in general, see the authentication documentation. which is this link...:

http://code.google.com/apis/gdata/docs/auth/overview.html  

...which states: "AuthSub and ClientLogin are Google's proprietary authorization APIs, available as an alternative to OAuth for most Google APIs. If possible, you should avoid using these services. If you already have applications that use them, you should migrate to the recommended options described above."

So first question: should you use OAuth 2.0?

When I attempted to get an authsub token here:

https://www.google.com/accounts/ManageDomains

I was given a “OAuth Consumer Key” for my Google sites url.  Then i was able to “Test your AuthSub registration”

https://www.google.com/accounts/UpdateDomain

...the message came back.”The page you have requested cannot be displayed. Another site was requesting access to your Google Account, but sent a malformed request. Please contact the site that you were trying to use when you received this message to inform them of the error. A detailed error message follows: AuthSub target path prefix does not match the provided "next" URL.”

Which seems to to looking for a Google “calandar” site in the URI for some reason.  Does a Google Sites URL work for "test your AuthSub resgistration”?