Windows AD UME with SAP NW portal 7.4 with different back end user id's

Hi All,

We have installed SAP NW 7.4 and configure SSO for our back end systems ( ERP, BI and Solution manager ).

So we want to use it with Windows AD users as UME to NW 7.4 portal, we have configured in portal. But in the back end ERP, BI and Solution manager we have same user with different ID.

For example in Windows AD we have SSOTEST, same user has TESTSSO in ERP, SSOUSER in BI and USERSSO in solution manager.

Some where i read that we can create any number of aliases for a single user in Windows AD. But our AD admin saying that the option is not available.

Please suggest how we can configure for different users.

Regards,

Sree