Series 7 integration with C8

[sesera1]

Hi there,
We have Series 7 integrated with Cognos 8 and when drilling through from a PowerPlay cube to a C8 report the users get prompted to authenticate again.
We had a similar setup with ReportNet and Series 7 and there were no problems, but since we upgraded to C8 the single sign on doesn't work as expected.

Any help would be appreciated.
Thank you.