EP to BW SSO does not work for BW Report iView

I can't get SSO to work for BW Report iViews. Each time I hit the iView I am prompted for the userid/password. After I enter the credentials, the iView renders correctly.

I created an SAP Transaction iView using the same system and the SSO works just fine.

I have read several forum discussions and blogs, but I still have not found the solution. Any suggests would be appreciated.

Thanks.