I have a Portal system (Java stack, NW04s) that has an iView of type webDynpro ABAP. The custom Web Dynpro ABAP application resides on another system (ABAP stack, running ECC6). We have configured the trust relationship between the Portal and the ECC system as per
http://help.sap.com/saphelp_nw04s/helpdata/en/61/42897de269cf44b35f9395978cc9cb/content.htm
We know this is working since we are able to run ESS. However, for the custom WebDynpro ABAP application, when calling it for the first time, a logon screen shows up. How can we get rid of it? what are we missing to have SSO work for the custom WebDynpro application?