Are all the IBX gurus on holiday or something? Like Artur I am an IBOer and
have no problems, but I seem to remember reading something about stripping
off the rdb$ for one field, and that may well be rdb$db_key. So try to
select db_key rather than rdb$db_key and see if that solves your problem.

Set
-sometimes writing a slogan is harder than answering the question