AzMan Error: This operation can not be performed on the current domain.

So here is my setup:

I am authenticating against our main domain, but the website is hosted on another domain. There is a full trust relationship between the two. I am trying to use Basic Authentication (in IIS) and have specified the default domain. I am able to authenticate but any call to the role manager causes this error:

This operation can not be performed on the current domain.

How can I have AzMan work across domains?

Thanks!
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