Dave, Mark, thanks for the helpful suggestions! Just to make sure I understood what you meant, Dave: Your workaround for the multi-site and variable URI, is to host a simple server with a fixed URI, which all the other sites go through for authenticating with your OAuth server. The redirect will then always go back to that static host, and the clients which contacted the static-server will then proceed to acquire the token by JavaScript or some other way, correct? So say we got 2 users, example1.com and example2.com, and our static authentication server helper-example.com. Using this workaround, example1.com and example2.com should both be able to authenticate by opening a window and fetching the token from helper-example.com, which in turn got both tokens from your(Constant Contact) OAuth server.
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