We never got it to work after many attempts in our two-domain-crossing-over scenario and went with a third party solution from eRequester that is an add-in to GP. It was a modest-middle price app but our customer wanted the features and willing to pay. I would think that some of the suggestions offered in this thread should work under certain configurations. All I could suggest is after trail and error with the different recommendations offered and still no resolution, call and submit a support case to Microsoft.
Cheers