I have integrated SRM 5.0 with SAP EP 7.0 (2004s SP11).
Then i assign the Shop transaction (bbpsc02) from within the portal in the following steps (described below) the asks for a user name and password and in the dialog box it show the instance id of SRM.
Steps to reconstruct
1. Execute the transaction bbpsc02 (shop)
2. Click on describe requirement, enter the fields and click on add to shopping cart.
3. Click on the magnify icon (Details icon under the action column)
4. Expand the documents and attachments section.
5. Click on search & add.
the password popup come up at this step.
SSO has been configured between the systems.
Any help will be appreciated.