ASP.Net 2.0 ReportViewer

I have been fighting an authentication problem on this all day with the new ReportViewer in ASP.Net 2.0.

I have been getting 401 authorisation errors when I tried to set any parameters (or run a report with no parameters) inside the viewer.

Turns out the problem was that the _ReportViewer1.ServerReport.ReportServerUrl _ was set to http://test1.mydomain.com/ReportServer, if I changed it to http://locahost/ReportServer it all leapt into live, even though they should both resolve to the same server, and both work if I browser there with IE.

Well it is a solution for now, but not I long term one I guess.