If you're getting "Could not initialize proxy - no Session" exceptions when trying to access a domain object's collection of child objects, check that you aren't storing the domain object in a HTTP session, as when model objects are stored in the session, they're detached. Prior to version 1.0.3, the detached object had enough information as it was "eagerly fetched". With 1.0.4, this is no longer the case as it's just a proxied object.
user.profiles // Then doing stuff like this won't throw the error anymore
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