For ActAs, the username on behalf of whom a client requests for a token must be present in the user store (eDirectory). The default implementation checks for this user only in the default user store. If you want to search the user in a different user store, perform the following steps:
Click Devices > Identity Server > Edit > Local > Classes.
Click New and specify the following details:
Display name: Specify Find_By_Username
Java class: Select Other
Java class path: Specify com.novell.nidp.authentication.local.UserNameAuthenticationClass
Click Next > Finish.
Go to Local > Methods.
Click New and select the Find_By_Username class.
For information about configuring a method, see Configuring Authentication Methods.
Go to WS-Trust > STS Configuration. Move this authentication method in Selected Authentication Methods from Available Authentication Methods.