Same username in two different authentication providers

WebLogic 10.3.6

My configuration has one security realm with 3 authentication providers, SAML, custom LDAP and the default authenticator.  I have a user that is present in the custom LDAP authenticator but need to create that same username in the default authenticator.  The reason is that the custom LDAP is used only in conjunction with SAML authentication and I have a need to authenticate as the user using username/password for testing purposes.

I see that a username must be unique in a realm.  I also see that it is possible for two authentication providers to use the same backend store each presenting the same usernames.  What I need to do is create a user account in the default authenticator that already exists in another authenticator.