Anstelle des Lookups würde ich mit @UserNameList arbeiten:
For a database on a server or a local database with "Enforce a consistent Access Control List across all replicas" in effect, @UserNamesList returns a text list containing the following information for the current user:
Common name
All hierarchical names (fully distinguished) that include the user name; for example, CN=My Name/OU=My Org Unit/O=My Org, plus */OU=My Org Unit/O=My Org, */O=My Org, and *
Any roles associated with the user in the ACL
All groups to which the user belongs (only if the database is on a server)
Note This @Function is new with Release 5.
Syntax
@UserNamesList
Damit kannst Du dann alles erschlagen ;-)
Andreas