What happens when the person who installed and configured your MOSS or EPM solution is not there, and you need to access the SSP admin pages ?You get an access error. 

By default only the setup account that was used to create the SSP (also know as farms's shared service), is allowed to access the SSP admin pages on the Shared Services Admin site..

It is a good practice to define at least another SSP administrator.

To change the permission settings, use the SharePoint Site Actions Menu (on the right), and select Advanced Permissions in the Users and Permissions topic.

By default you only see the windows account used during the setup.

 Add another windows Account with full control